diff --git a/CHANGES b/CHANGES
index 1aeb27254..f1c57a24d 100644
--- a/CHANGES
+++ b/CHANGES
@@ -18,6 +18,8 @@ Features added
 * #10755: linkcheck: Check the source URL of raw directives that use the ``url``
   option.
 * #10781: Allow :rst:role:`ref` role to be used with definitions and fields.
+* #10717: HTML Search: Increase priority for full title and 
+  subtitle matches in search results
 
 Bugs fixed
 ----------
diff --git a/sphinx/environment/__init__.py b/sphinx/environment/__init__.py
index 430e03358..1a1dd755f 100644
--- a/sphinx/environment/__init__.py
+++ b/sphinx/environment/__init__.py
@@ -59,7 +59,7 @@ if docutils.__version_info__[:2] <= (0, 17):
 
 # This is increased every time an environment attribute is added
 # or changed to properly invalidate pickle files.
-ENV_VERSION = 56
+ENV_VERSION = 57
 
 # config status
 CONFIG_OK = 1
diff --git a/sphinx/search/__init__.py b/sphinx/search/__init__.py
index ac8a44dcc..a3dd07d3f 100644
--- a/sphinx/search/__init__.py
+++ b/sphinx/search/__init__.py
@@ -183,6 +183,7 @@ class WordCollector(nodes.NodeVisitor):
     def __init__(self, document: nodes.document, lang: SearchLanguage) -> None:
         super().__init__(document)
         self.found_words: List[str] = []
+        self.found_titles: List[Tuple[str, str]] = []
         self.found_title_words: List[str] = []
         self.lang = lang
 
@@ -213,7 +214,10 @@ class WordCollector(nodes.NodeVisitor):
         elif isinstance(node, nodes.Text):
             self.found_words.extend(self.lang.split(node.astext()))
         elif isinstance(node, nodes.title):
-            self.found_title_words.extend(self.lang.split(node.astext()))
+            title = node.astext()
+            ids = node.parent['ids']
+            self.found_titles.append((title, ids[0] if ids else None))
+            self.found_title_words.extend(self.lang.split(title))
         elif isinstance(node, Element) and self.is_meta_keywords(node):
             keywords = node['content']
             keywords = [keyword.strip() for keyword in keywords.split(',')]
@@ -237,6 +241,7 @@ class IndexBuilder:
         self._mapping: Dict[str, Set[str]] = {}     # stemmed word -> set(docname)
         # stemmed words in titles -> set(docname)
         self._title_mapping: Dict[str, Set[str]] = {}
+        self._all_titles: Dict[str, List[Tuple[str, str]]] = {}  # docname -> all titles
         self._stem_cache: Dict[str, str] = {}       # word -> stemmed word
         self._objtypes: Dict[Tuple[str, str], int] = {}     # objtype -> index
         # objtype index -> (domain, type, objname (localized))
@@ -281,6 +286,11 @@ class IndexBuilder:
         index2fn = frozen['docnames']
         self._filenames = dict(zip(index2fn, frozen['filenames']))
         self._titles = dict(zip(index2fn, frozen['titles']))
+        self._all_titles = {}
+
+        for title, doc_tuples in frozen['alltitles'].items():
+            for doc, titleid in doc_tuples:
+                self._all_titles.setdefault(index2fn[doc], []).append((title, titleid))
 
         def load_terms(mapping: Dict[str, Any]) -> Dict[str, Set[str]]:
             rv = {}
@@ -364,9 +374,16 @@ class IndexBuilder:
         objects = self.get_objects(fn2index)  # populates _objtypes
         objtypes = {v: k[0] + ':' + k[1] for (k, v) in self._objtypes.items()}
         objnames = self._objnames
+
+        alltitles: Dict[str, List[Tuple[int, str]]] = {}
+        for docname, titlelist in self._all_titles.items():
+            for title, titleid in titlelist:
+                alltitles.setdefault(title.lower(), []).append((fn2index[docname],  titleid))
+
         return dict(docnames=docnames, filenames=filenames, titles=titles, terms=terms,
                     objects=objects, objtypes=objtypes, objnames=objnames,
-                    titleterms=title_terms, envversion=self.env.version)
+                    titleterms=title_terms, envversion=self.env.version,
+                    alltitles=alltitles)
 
     def label(self) -> str:
         return "%s (code: %s)" % (self.lang.language_name, self.lang.lang)
@@ -374,13 +391,16 @@ class IndexBuilder:
     def prune(self, docnames: Iterable[str]) -> None:
         """Remove data for all docnames not in the list."""
         new_titles = {}
+        new_alltitles = {}
         new_filenames = {}
         for docname in docnames:
             if docname in self._titles:
                 new_titles[docname] = self._titles[docname]
+                new_alltitles[docname] = self._all_titles[docname]
                 new_filenames[docname] = self._filenames[docname]
         self._titles = new_titles
         self._filenames = new_filenames
+        self._all_titles = new_alltitles
         for wordnames in self._mapping.values():
             wordnames.intersection_update(docnames)
         for wordnames in self._title_mapping.values():
@@ -403,6 +423,8 @@ class IndexBuilder:
                 return self._stem_cache[word]
         _filter = self.lang.word_filter
 
+        self._all_titles[docname] = visitor.found_titles
+
         for word in visitor.found_title_words:
             stemmed_word = stem(word)
             if _filter(stemmed_word):
diff --git a/sphinx/themes/basic/static/searchtools.js b/sphinx/themes/basic/static/searchtools.js
index f2fb7d5cf..30872aa8f 100644
--- a/sphinx/themes/basic/static/searchtools.js
+++ b/sphinx/themes/basic/static/searchtools.js
@@ -237,6 +237,11 @@ const Search = {
    * execute search (requires search index to be loaded)
    */
   query: (query) => {
+    const filenames = Search._index.filenames;
+    const docNames = Search._index.docnames;
+    const titles = Search._index.titles;
+    const allTitles = Search._index.alltitles;
+
     // stem the search terms and add them to the correct list
     const stemmer = new Stemmer();
     const searchTerms = new Set();
@@ -272,6 +277,23 @@ const Search = {
     let results = [];
     _removeChildren(document.getElementById("search-progress"));
 
+    const queryLower = query.toLowerCase();
+    for (const [title, foundTitles] of Object.entries(allTitles)) {
+      if (title.includes(queryLower) && (queryLower.length >= title.length/2)) {
+        for (const [file, id] of foundTitles) {
+          let score = Math.round(100 * queryLower.length / title.length)
+          results.push([
+            docNames[file],
+            titles[file],
+            id !== null ? "#" + id : "",
+            null,
+            score,
+            filenames[file],
+          ]);
+        }
+      }
+    }
+
     // lookup as object
     objectTerms.forEach((term) =>
       results.push(...Search.performObjectSearch(term, objectTerms))
@@ -399,8 +421,8 @@ const Search = {
     // prepare search
     const terms = Search._index.terms;
     const titleTerms = Search._index.titleterms;
-    const docNames = Search._index.docnames;
     const filenames = Search._index.filenames;
+    const docNames = Search._index.docnames;
     const titles = Search._index.titles;
 
     const scoreMap = new Map();
diff --git a/tests/test_search.py b/tests/test_search.py
index 0330bfbae..cbe1be54f 100644
--- a/tests/test_search.py
+++ b/tests/test_search.py
@@ -177,7 +177,8 @@ def test_IndexBuilder():
                   'non': [0, 1, 2, 3],
                   'test': [0, 1, 2, 3]},
         'titles': ('title1_1', 'title1_2', 'title2_1', 'title2_2'),
-        'titleterms': {'section_titl': [0, 1, 2, 3]}
+        'titleterms': {'section_titl': [0, 1, 2, 3]},
+        'alltitles': {'section_title': [(0, 'section-title'), (1, 'section-title'), (2, 'section-title'), (3, 'section-title')]}
     }
     assert index._objtypes == {('dummy1', 'objtype1'): 0, ('dummy2', 'objtype1'): 1}
     assert index._objnames == {0: ('dummy1', 'objtype1', 'objtype1'),
@@ -234,7 +235,8 @@ def test_IndexBuilder():
                   'non': [0, 1],
                   'test': [0, 1]},
         'titles': ('title1_2', 'title2_2'),
-        'titleterms': {'section_titl': [0, 1]}
+        'titleterms': {'section_titl': [0, 1]},
+        'alltitles': {'section_title': [(0, 'section-title'), (1, 'section-title')]}
     }
     assert index._objtypes == {('dummy1', 'objtype1'): 0, ('dummy2', 'objtype1'): 1}
     assert index._objnames == {0: ('dummy1', 'objtype1', 'objtype1'),