diff --git a/CHANGELOG.md b/CHANGELOG.md
index 7d11efa..f7317c7 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -58,6 +58,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 		- automatic meta cache reset after main `process()` call (performance optimization) replaced with `reset()`
 		  method
 		- properties are not set/unset via closure binding when public
+		- call `unset()` for mapped object properties only in `RequiredFields::none()` mode (performance optimization)
 
 ### Removed
 
diff --git a/src/Processing/DefaultProcessor.php b/src/Processing/DefaultProcessor.php
index b88f5dd..4fc72a2 100644
--- a/src/Processing/DefaultProcessor.php
+++ b/src/Processing/DefaultProcessor.php
@@ -552,10 +552,13 @@ private function fillObject(
 			$this->rawValuesMap->setRawValues($object, $rawData);
 		}
 
-		// Reset mapped properties state
 		$fieldsMeta = $meta->getFields();
-		foreach ($fieldsMeta as $fieldMeta) {
-			$this->objectUnset($object, $fieldMeta->getProperty());
+
+		if ($dynamic->getOptions()->getRequiredFields() === RequiredFields::none()) {
+			// Reset mapped properties state
+			foreach ($fieldsMeta as $fieldMeta) {
+				$this->objectUnset($object, $fieldMeta->getProperty());
+			}
 		}
 
 		// Set processed data