diff --git a/core/queryparser/sparql/src/main/java/org/eclipse/rdf4j/query/parser/sparql/TupleExprBuilder.java b/core/queryparser/sparql/src/main/java/org/eclipse/rdf4j/query/parser/sparql/TupleExprBuilder.java
index 0578f7152a9..a76e9143629 100644
--- a/core/queryparser/sparql/src/main/java/org/eclipse/rdf4j/query/parser/sparql/TupleExprBuilder.java
+++ b/core/queryparser/sparql/src/main/java/org/eclipse/rdf4j/query/parser/sparql/TupleExprBuilder.java
@@ -686,8 +686,9 @@ public TupleExpr visit(ASTSelect node, Object data) throws VisitorException {
 
 	private static boolean isIllegalCombinedWithGroupByExpression(ValueExpr expr, List<ProjectionElem> elements,
 			Set<String> groupNames) {
-		if (expr instanceof ValueConstant)
+		if (expr instanceof ValueConstant) {
 			return false;
+		}
 
 		VarNameCollector varNameCollector = new VarNameCollector();
 		expr.visit(varNameCollector);
@@ -704,6 +705,10 @@ private static boolean isIllegalCombinedWithGroupByExpression(ValueExpr expr, Li
 
 	private static boolean isIllegalCombinedWithGroupByExpression(String varName, List<ProjectionElem> elements,
 			Set<String> groupNames) {
+		if (groupNames.contains(varName)) {
+			return false;
+		}
+
 		do {
 			String prev = varName;
 
diff --git a/core/queryparser/sparql/src/test/java/org/eclipse/rdf4j/query/parser/sparql/SPARQLParserTest.java b/core/queryparser/sparql/src/test/java/org/eclipse/rdf4j/query/parser/sparql/SPARQLParserTest.java
index 2a2b48b6b1b..4097b924db9 100644
--- a/core/queryparser/sparql/src/test/java/org/eclipse/rdf4j/query/parser/sparql/SPARQLParserTest.java
+++ b/core/queryparser/sparql/src/test/java/org/eclipse/rdf4j/query/parser/sparql/SPARQLParserTest.java
@@ -517,4 +517,14 @@ public void testGroupByProjectionHandling_renameVariableWithAggregation() {
 		parser.parseQuery(query, null);
 	}
 
+	@Test
+	public void testGroupByProjectionHandling_function() {
+		String query = "select (strlen(concat(strlen(?s)+2, \"abc\", count(?o))) as ?len) where { \n" +
+				"?s ?p ?o .\n" +
+				"} group by ?s";
+
+		// should parse without error
+		parser.parseQuery(query, null);
+	}
+
 }