diff --git a/lib/Doctrine/ORM/Query/ResultSetMappingBuilder.php b/lib/Doctrine/ORM/Query/ResultSetMappingBuilder.php
index 65618a9ef7d..4643012846c 100644
--- a/lib/Doctrine/ORM/Query/ResultSetMappingBuilder.php
+++ b/lib/Doctrine/ORM/Query/ResultSetMappingBuilder.php
@@ -4,6 +4,7 @@
 
 namespace Doctrine\ORM\Query;
 
+use Doctrine\DBAL\Types\Type;
 use Doctrine\ORM\EntityManagerInterface;
 use Doctrine\ORM\Internal\SQLResultCasing;
 use Doctrine\ORM\Mapping\ClassMetadataInfo;
@@ -16,6 +17,7 @@
 use function sprintf;
 use function strpos;
 use function strtolower;
+use function var_dump;
 
 /**
  * A ResultSetMappingBuilder uses the EntityManager to automatically populate entity fields.
@@ -432,19 +434,26 @@ public function generateSelectClause($tableAliases = [])
         foreach ($this->columnOwnerMap as $columnName => $dqlAlias) {
             $tableAlias = $tableAliases[$dqlAlias] ?? $dqlAlias;
 
-            if ($sql) {
+            if ($sql !== '') {
                 $sql .= ', ';
             }
 
-            $sql .= $tableAlias . '.';
-
             if (isset($this->fieldMappings[$columnName])) {
-                $class = $this->em->getClassMetadata($this->declaringClasses[$columnName]);
-                $sql  .= $class->fieldMappings[$this->fieldMappings[$columnName]]['columnName'];
+                $class             = $this->em->getClassMetadata($this->declaringClasses[$columnName]);
+                $fieldName         = $this->fieldMappings[$columnName];
+                $classFieldMapping = $class->fieldMappings[$fieldName];
+                $columnSql         = $tableAlias . '.' . $classFieldMapping['columnName'];
+
+                if (isset($classFieldMapping['requireSQLConversion']) && $classFieldMapping['requireSQLConversion'] === true) {
+                    $type      = Type::getType($classFieldMapping['type']);
+                    $columnSql = $type->convertToPHPValueSQL($columnSql, $this->em->getConnection()->getDatabasePlatform());
+                }
+
+                $sql .= $columnSql;
             } elseif (isset($this->metaMappings[$columnName])) {
-                $sql .= $this->metaMappings[$columnName];
+                $sql .= $tableAlias . '.' . $this->metaMappings[$columnName];
             } elseif (isset($this->discriminatorColumns[$dqlAlias])) {
-                $sql .= $this->discriminatorColumns[$dqlAlias];
+                $sql .= $tableAlias . '.' . $this->discriminatorColumns[$dqlAlias];
             }
 
             $sql .= ' AS ' . $columnName;
diff --git a/tests/Doctrine/Tests/ORM/Functional/NativeQueryTest.php b/tests/Doctrine/Tests/ORM/Functional/NativeQueryTest.php
index f69c91867e9..ff773413695 100644
--- a/tests/Doctrine/Tests/ORM/Functional/NativeQueryTest.php
+++ b/tests/Doctrine/Tests/ORM/Functional/NativeQueryTest.php
@@ -6,6 +6,7 @@
 
 use Doctrine\Common\Collections\ArrayCollection;
 use Doctrine\DBAL\Platforms\AbstractPlatform;
+use Doctrine\DBAL\Types\Type as DBALType;
 use Doctrine\Deprecations\PHPUnit\VerifyDeprecations;
 use Doctrine\ORM\Internal\Hydration\HydrationException;
 use Doctrine\ORM\Internal\SQLResultCasing;
@@ -13,6 +14,7 @@
 use Doctrine\ORM\Query\Parameter;
 use Doctrine\ORM\Query\ResultSetMapping;
 use Doctrine\ORM\Query\ResultSetMappingBuilder;
+use Doctrine\Tests\DbalTypes\UpperCaseStringType;
 use Doctrine\Tests\Models\CMS\CmsAddress;
 use Doctrine\Tests\Models\CMS\CmsEmail;
 use Doctrine\Tests\Models\CMS\CmsPhonenumber;
@@ -22,6 +24,7 @@
 use Doctrine\Tests\Models\Company\CompanyFixContract;
 use Doctrine\Tests\Models\Company\CompanyFlexContract;
 use Doctrine\Tests\Models\Company\CompanyPerson;
+use Doctrine\Tests\Models\CustomType\CustomTypeUpperCase;
 use Doctrine\Tests\Models\DDC3899\DDC3899FixContract;
 use Doctrine\Tests\Models\DDC3899\DDC3899User;
 use Doctrine\Tests\OrmFunctionalTestCase;
@@ -796,4 +799,38 @@ public function testGenerateSelectClauseWithDiscriminatorColumn(): void
 
         $this->assertSQLEquals('u1.id as id, c1.discr as discr', $selectClause);
     }
+
+    public function testGenerateSelectClauseWithCustomTypeUsingEntityFromClassMetadata(): void
+    {
+        if (DBALType::hasType('upper_case_string')) {
+            DBALType::overrideType('upper_case_string', UpperCaseStringType::class);
+        } else {
+            DBALType::addType('upper_case_string', UpperCaseStringType::class);
+        }
+
+        $rsm = new ResultSetMappingBuilder($this->_em, ResultSetMappingBuilder::COLUMN_RENAMING_INCREMENT);
+
+        $rsm->addRootEntityFromClassMetadata(CustomTypeUpperCase::class, 'ct');
+
+        $selectClause = $rsm->generateSelectClause(['ct' => 'ct1']);
+
+        $this->assertSQLEquals('ct1.id as id0, lower(ct1.lowercasestring) as lowercasestring1, lower(ct1.named_lower_case_string) as named_lower_case_string2', $selectClause);
+    }
+
+    public function testGenerateSelectClauseWithCustomTypeUsingAddFieldResult(): void
+    {
+        if (DBALType::hasType('upper_case_string')) {
+            DBALType::overrideType('upper_case_string', UpperCaseStringType::class);
+        } else {
+            DBALType::addType('upper_case_string', UpperCaseStringType::class);
+        }
+
+        $rsm = new ResultSetMappingBuilder($this->_em, ResultSetMappingBuilder::COLUMN_RENAMING_INCREMENT);
+        $rsm->addEntityResult(CustomTypeUpperCase::class, 'ct');
+        $rsm->addFieldResult('ct', $this->getSQLResultCasing($this->platform, 'lowercasestring'), 'lowerCaseString');
+
+        $selectClause = $rsm->generateSelectClause(['ct' => 'ct1']);
+
+        $this->assertSQLEquals('lower(ct1.lowercasestring) as lowercasestring', $selectClause);
+    }
 }