diff --git a/inference-engine/cmake/developer_package_config.cmake.in b/inference-engine/cmake/developer_package_config.cmake.in
index df2ccac827d..a20b334cb0c 100644
--- a/inference-engine/cmake/developer_package_config.cmake.in
+++ b/inference-engine/cmake/developer_package_config.cmake.in
@@ -32,6 +32,10 @@ set(GNA "@GNA@")
 
 include("${CMAKE_CURRENT_LIST_DIR}/targets_developer.cmake")
 
+# for compatibility
+set_property(TARGET IE::inference_engine_legacy APPEND PROPERTY
+    INTERFACE_INCLUDE_DIRECTORIES "${IE_MAIN_SOURCE_DIR}/src/legacy_api/include/legacy")
+
 # to allow too create ALIAS for IE::inference_engine in 3rd-party projects
 set_property(TARGET IE::inference_engine PROPERTY IMPORTED_GLOBAL TRUE)
 
diff --git a/inference-engine/src/cldnn_engine/cldnn_executable_network.cpp b/inference-engine/src/cldnn_engine/cldnn_executable_network.cpp
index b3f245b3e3c..f0c1b190efc 100644
--- a/inference-engine/src/cldnn_engine/cldnn_executable_network.cpp
+++ b/inference-engine/src/cldnn_engine/cldnn_executable_network.cpp
@@ -17,7 +17,6 @@
 #include <description_buffer.hpp>
 #include <cldnn/cldnn_config.hpp>
 #include <legacy/graph_tools.hpp>
-#include <legacy/ie_layers_internal.hpp>
 #include <legacy/net_pass.h>
 #include "cldnn_infer_request.h"
 #include <threading/ie_executor_manager.hpp>
diff --git a/inference-engine/src/cldnn_engine/cldnn_graph.cpp b/inference-engine/src/cldnn_engine/cldnn_graph.cpp
index 4868f87a4fe..673b1272871 100644
--- a/inference-engine/src/cldnn_engine/cldnn_graph.cpp
+++ b/inference-engine/src/cldnn_engine/cldnn_graph.cpp
@@ -18,7 +18,6 @@
 #include <description_buffer.hpp>
 #include <cldnn/cldnn_config.hpp>
 #include <legacy/graph_tools.hpp>
-#include <legacy/ie_layers_internal.hpp>
 #include <legacy/net_pass.h>
 #include "cldnn_infer_request.h"
 #include <threading/ie_executor_manager.hpp>
@@ -27,7 +26,7 @@
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <exec_graph_info.hpp>
-#include "ie_ngraph_utils.hpp"
+#include <legacy/ie_ngraph_utils.hpp>
 #include "generic_ie.hpp"
 #include <ngraph/variant.hpp>
 
diff --git a/inference-engine/src/gna_plugin/backend/dnn_components.cpp b/inference-engine/src/gna_plugin/backend/dnn_components.cpp
index 76df4d0ac38..bfff0888484 100644
--- a/inference-engine/src/gna_plugin/backend/dnn_components.cpp
+++ b/inference-engine/src/gna_plugin/backend/dnn_components.cpp
@@ -8,7 +8,7 @@
 #include <ie_common.h>
 #include <legacy/ie_layers.h>
 #include <iomanip>
-#include <details/caseless.hpp>
+#include <caseless.hpp>
 #include <layers/gna_copy_layer.hpp>
 #include "backend/dnn_types.h"
 
diff --git a/inference-engine/src/gna_plugin/connection_details.hpp b/inference-engine/src/gna_plugin/connection_details.hpp
index 71bdf9de504..01a34050451 100644
--- a/inference-engine/src/gna_plugin/connection_details.hpp
+++ b/inference-engine/src/gna_plugin/connection_details.hpp
@@ -4,7 +4,7 @@
 
 #pragma once
 
-#include "ie_layers.h"
+#include <legacy/ie_layers.h>
 
 namespace GNAPluginNS {
 struct ConnectionDetails {
diff --git a/inference-engine/src/gna_plugin/gna_graph_compiler.hpp b/inference-engine/src/gna_plugin/gna_graph_compiler.hpp
index 8f310ab5cc0..9f8e65e531c 100644
--- a/inference-engine/src/gna_plugin/gna_graph_compiler.hpp
+++ b/inference-engine/src/gna_plugin/gna_graph_compiler.hpp
@@ -11,9 +11,7 @@
 #include <string>
 #include <vector>
 
-#include "ie_layers.h"
-#include <ie_data.h>
-#include <ie_common.h>
+#include <legacy/ie_layers.h>
 #include "descriptions/gna_input_desc.hpp"
 #include "descriptions/gna_flags.hpp"
 #include "connection_details.hpp"
diff --git a/inference-engine/src/gna_plugin/layers/gna_concat_layer.hpp b/inference-engine/src/gna_plugin/layers/gna_concat_layer.hpp
index 4c64611e5e3..7c714317bf8 100644
--- a/inference-engine/src/gna_plugin/layers/gna_concat_layer.hpp
+++ b/inference-engine/src/gna_plugin/layers/gna_concat_layer.hpp
@@ -7,7 +7,7 @@
 #include <string>
 #include <vector>
 
-#include "ie_layers.h"
+#include <legacy/ie_layers.h>
 
 namespace GNAPluginNS {
 class GNAConcatLayer {
diff --git a/inference-engine/src/gna_plugin/layers/gna_crop_layer.hpp b/inference-engine/src/gna_plugin/layers/gna_crop_layer.hpp
index 130a189dcc4..248ba9ecde5 100644
--- a/inference-engine/src/gna_plugin/layers/gna_crop_layer.hpp
+++ b/inference-engine/src/gna_plugin/layers/gna_crop_layer.hpp
@@ -4,7 +4,7 @@
 
 #pragma once
 
-#include "ie_layers.h"
+#include <legacy/ie_layers.h>
 
 namespace GNAPluginNS {
 class GNACropLayer {
diff --git a/inference-engine/src/gna_plugin/layers/gna_layer_info.hpp b/inference-engine/src/gna_plugin/layers/gna_layer_info.hpp
index 8f5fb4b0c8a..4732eb40403 100644
--- a/inference-engine/src/gna_plugin/layers/gna_layer_info.hpp
+++ b/inference-engine/src/gna_plugin/layers/gna_layer_info.hpp
@@ -7,7 +7,7 @@
 #include <string>
 #include <memory>
 #include <vector>
-#include "ie_layers.h"
+#include <legacy/ie_layers.h>
 #include "caseless.hpp"
 #include "ie_algorithm.hpp"
 #include "backend/gna_types.h"
diff --git a/inference-engine/src/gna_plugin/layers/gna_memory_layer.hpp b/inference-engine/src/gna_plugin/layers/gna_memory_layer.hpp
index 93d656e84f5..6ead05c0401 100644
--- a/inference-engine/src/gna_plugin/layers/gna_memory_layer.hpp
+++ b/inference-engine/src/gna_plugin/layers/gna_memory_layer.hpp
@@ -4,7 +4,7 @@
 
 #pragma once
 
-#include "ie_layers.h"
+#include <legacy/ie_layers.h>
 
 namespace GNAPluginNS {
 /**
diff --git a/inference-engine/src/hetero_plugin/hetero_executable_network.cpp b/inference-engine/src/hetero_plugin/hetero_executable_network.cpp
index 2e1063a5f89..ed460b0e9e0 100644
--- a/inference-engine/src/hetero_plugin/hetero_executable_network.cpp
+++ b/inference-engine/src/hetero_plugin/hetero_executable_network.cpp
@@ -23,7 +23,7 @@
 #include <array>
 #include <cstdint>
 
-#include "ie_ngraph_utils.hpp"
+#include "legacy/ie_ngraph_utils.hpp"
 #include "ie_plugin_config.hpp"
 #include "cpp_interfaces/interface/ie_internal_plugin_config.hpp"
 #include "hetero/hetero_plugin_config.hpp"
diff --git a/inference-engine/src/inference_engine/CMakeLists.txt b/inference-engine/src/inference_engine/CMakeLists.txt
index 386e4940e56..7de2e760e53 100644
--- a/inference-engine/src/inference_engine/CMakeLists.txt
+++ b/inference-engine/src/inference_engine/CMakeLists.txt
@@ -104,7 +104,6 @@ add_library(${TARGET_NAME}_plugin_api INTERFACE)
 target_include_directories(${TARGET_NAME}_plugin_api INTERFACE
     "${IE_MAIN_SOURCE_DIR}/src/plugin_api"
     "${IE_MAIN_SOURCE_DIR}/src/legacy_api/include"
-    "${IE_MAIN_SOURCE_DIR}/src/legacy_api/include/legacy" # for compatibility
     $<TARGET_PROPERTY:${TARGET_NAME}_preproc,INTERFACE_INCLUDE_DIRECTORIES>
     ${PUBLIC_HEADERS_DIR})
 
diff --git a/inference-engine/src/inference_engine/shape_infer/ie_priorgridgenerator_onnx_shape_infer.hpp b/inference-engine/src/inference_engine/shape_infer/ie_priorgridgenerator_onnx_shape_infer.hpp
index f97bf89a82a..e19ea48dac9 100644
--- a/inference-engine/src/inference_engine/shape_infer/ie_priorgridgenerator_onnx_shape_infer.hpp
+++ b/inference-engine/src/inference_engine/shape_infer/ie_priorgridgenerator_onnx_shape_infer.hpp
@@ -4,8 +4,6 @@
 
 #pragma once
 
-#include <ie_layers.h>
-
 #include <description_buffer.hpp>
 #include <map>
 #include <memory>
diff --git a/inference-engine/src/mkldnn_plugin/nodes/mkldnn_interpolate_node.cpp b/inference-engine/src/mkldnn_plugin/nodes/mkldnn_interpolate_node.cpp
index 9d801db8447..ad34f2f1c64 100644
--- a/inference-engine/src/mkldnn_plugin/nodes/mkldnn_interpolate_node.cpp
+++ b/inference-engine/src/mkldnn_plugin/nodes/mkldnn_interpolate_node.cpp
@@ -7,13 +7,13 @@
 #include "mkldnn_quantize_node.h"
 #include "mkldnn_depthwise_node.h"
 #include "mkldnn_activation_node.h"
-#include <ie_layers.h>
+#include <legacy/ie_layers.h>
 #include <mkldnn.hpp>
 #include <string>
 #include <vector>
 #include <mkldnn_types.h>
 #include <mkldnn_extension_utils.h>
-#include <ie_layers_internal.hpp>
+#include <legacy/ie_layers_internal.hpp>
 #include "ie_parallel.hpp"
 #include <algorithm>
 
diff --git a/inference-engine/src/mkldnn_plugin/nodes/mkldnn_reduce_node.cpp b/inference-engine/src/mkldnn_plugin/nodes/mkldnn_reduce_node.cpp
index 23eac1b5ee6..c2f941a2084 100644
--- a/inference-engine/src/mkldnn_plugin/nodes/mkldnn_reduce_node.cpp
+++ b/inference-engine/src/mkldnn_plugin/nodes/mkldnn_reduce_node.cpp
@@ -7,13 +7,12 @@
 #include "mkldnn_quantize_node.h"
 #include "mkldnn_depthwise_node.h"
 #include "mkldnn_activation_node.h"
-#include <ie_layers.h>
+#include <legacy/ie_layers.h>
 #include <mkldnn.hpp>
 #include <string>
 #include <vector>
 #include <mkldnn_types.h>
 #include <mkldnn_extension_utils.h>
-#include <ie_layers_internal.hpp>
 #include "ie_parallel.hpp"
 #include <algorithm>
 
diff --git a/inference-engine/src/plugin_api/cpp_interfaces/interface/ie_iplugin_internal.hpp b/inference-engine/src/plugin_api/cpp_interfaces/interface/ie_iplugin_internal.hpp
index c8833f4511f..530c81bdb3e 100644
--- a/inference-engine/src/plugin_api/cpp_interfaces/interface/ie_iplugin_internal.hpp
+++ b/inference-engine/src/plugin_api/cpp_interfaces/interface/ie_iplugin_internal.hpp
@@ -59,8 +59,6 @@ static void copyInputOutputInfo(const InputsDataMap & networkInputs, const Outpu
     _networkInputs.clear();
     _networkOutputs.clear();
 
-    IE_SUPPRESS_DEPRECATED_START
-
     for (const auto& it : networkInputs) {
         InputInfo::Ptr newPtr;
         if (it.second) {
@@ -78,8 +76,6 @@ static void copyInputOutputInfo(const InputsDataMap & networkInputs, const Outpu
         }
         _networkOutputs[it.first] = newData;
     }
-
-    IE_SUPPRESS_DEPRECATED_END
 }
 
 /**
diff --git a/inference-engine/src/plugin_api/details/caseless.hpp b/inference-engine/src/plugin_api/details/caseless.hpp
deleted file mode 100644
index 9cc661a457b..00000000000
--- a/inference-engine/src/plugin_api/details/caseless.hpp
+++ /dev/null
@@ -1,5 +0,0 @@
-// Copyright (C) 2018-2020 Intel Corporation
-// SPDX-License-Identifier: Apache-2.0
-//
-
-#include "../caseless.hpp"
diff --git a/inference-engine/tests/unit/cpu/bf16_transformer_test.cpp b/inference-engine/tests/unit/cpu/bf16_transformer_test.cpp
index d96a8437b43..7692c142326 100644
--- a/inference-engine/tests/unit/cpu/bf16_transformer_test.cpp
+++ b/inference-engine/tests/unit/cpu/bf16_transformer_test.cpp
@@ -8,9 +8,8 @@
 #include <ngraph/ngraph.hpp>
 #include <ngraph_ops/fully_connected.hpp>
 
-#include <inference_engine.hpp>
-#include <details/ie_cnn_network_tools.h>
-#include <convert_function_to_cnn_network.hpp>
+#include <legacy/details/ie_cnn_network_tools.h>
+#include <legacy/convert_function_to_cnn_network.hpp>
 #include <bf16transformer.h>
 
 using ngraph::Shape;