diff --git a/public/app/plugins/datasource/prometheus/promql.ts b/public/app/plugins/datasource/prometheus/promql.ts
index 6baa26d4899..c37f52796ba 100644
--- a/public/app/plugins/datasource/prometheus/promql.ts
+++ b/public/app/plugins/datasource/prometheus/promql.ts
@@ -238,6 +238,13 @@ export const FUNCTIONS = [
     documentation:
       'Returns the day of the week for each of the given times in UTC. Returned values are from 0 to 6, where 0 means Sunday etc.',
   },
+  {
+    insertText: 'day_of_year',
+    label: 'day_of_year',
+    detail: 'day_of_year(v=vector(time()) instant-vector)',
+    documentation:
+      'Returns the day of the year for each of the given times in UTC. Returned values are from 1 to 365 for non-leap years, and 1 to 366 in leap years.',
+  },
   {
     insertText: 'days_in_month',
     label: 'days_in_month',
diff --git a/public/app/plugins/datasource/prometheus/querybuilder/operations.ts b/public/app/plugins/datasource/prometheus/querybuilder/operations.ts
index 788689ee7da..2c091045bb2 100644
--- a/public/app/plugins/datasource/prometheus/querybuilder/operations.ts
+++ b/public/app/plugins/datasource/prometheus/querybuilder/operations.ts
@@ -164,6 +164,10 @@ export function getOperationDefinitions(): QueryBuilderOperationDef[] {
       id: PromOperationId.DayOfWeek,
       category: PromVisualQueryOperationCategory.Time,
     }),
+    createFunction({
+      id: PromOperationId.DayOfYear,
+      category: PromVisualQueryOperationCategory.Time,
+    }),
     createFunction({
       id: PromOperationId.DaysInMonth,
       category: PromVisualQueryOperationCategory.Time,
diff --git a/public/app/plugins/datasource/prometheus/querybuilder/types.ts b/public/app/plugins/datasource/prometheus/querybuilder/types.ts
index 49cef909698..24750f21a96 100644
--- a/public/app/plugins/datasource/prometheus/querybuilder/types.ts
+++ b/public/app/plugins/datasource/prometheus/querybuilder/types.ts
@@ -53,6 +53,7 @@ export enum PromOperationId {
   CountValues = 'count_values',
   DayOfMonth = 'day_of_month',
   DayOfWeek = 'day_of_week',
+  DayOfYear = 'day_of_year',
   DaysInMonth = 'days_in_month',
   Deg = 'deg',
   Delta = 'delta',