diff --git a/phpunit/functional/Glpi/Asset/CustomFieldDefinitionTest.php b/phpunit/functional/Glpi/Asset/CustomFieldDefinitionTest.php
index 1a5e758e5a0..ed65223dab4 100644
--- a/phpunit/functional/Glpi/Asset/CustomFieldDefinitionTest.php
+++ b/phpunit/functional/Glpi/Asset/CustomFieldDefinitionTest.php
@@ -229,6 +229,12 @@ public static function validateValueProvider()
                 'expected_value' => 'test',
                 'is_valid' => false,
             ],
+            [
+                'field_params' => ['type' => DateType::class],
+                'given_value' => '',
+                'expected_value' => null,
+                'is_valid' => true,
+            ],
             [
                 'field_params' => ['type' => DateTimeType::class],
                 'given_value' => '2021-01-01 00:00:00',
@@ -247,6 +253,12 @@ public static function validateValueProvider()
                 'expected_value' => 'test',
                 'is_valid' => false,
             ],
+            [
+                'field_params' => ['type' => DateTimeType::class],
+                'given_value' => '',
+                'expected_value' => null,
+                'is_valid' => true,
+            ],
         ];
     }
 
diff --git a/src/Glpi/Asset/CustomFieldType/DateTimeType.php b/src/Glpi/Asset/CustomFieldType/DateTimeType.php
index 2ab9254ba59..480d87f8c07 100644
--- a/src/Glpi/Asset/CustomFieldType/DateTimeType.php
+++ b/src/Glpi/Asset/CustomFieldType/DateTimeType.php
@@ -60,7 +60,7 @@ public function getFormInput(string $name, mixed $value, ?string $label = null,
 
     public function normalizeValue(mixed $value): ?string
     {
-        if ($value === null) {
+        if (empty($value)) {
             return null;
         }
         if (!preg_match('/^\d{4}-\d{2}-\d{2} \d{2}:\d{2}:\d{2}$/', $value)) {
@@ -71,7 +71,7 @@ public function normalizeValue(mixed $value): ?string
 
     public function formatValueFromDB(mixed $value): ?string
     {
-        if ($value === null || $value === '') {
+        if (empty($value)) {
             return null;
         }
         return date('Y-m-d H:i:s', strtotime($value . ' UTC'));
diff --git a/src/Glpi/Asset/CustomFieldType/DateType.php b/src/Glpi/Asset/CustomFieldType/DateType.php
index 523791ddb5e..bd83b4ee5a2 100644
--- a/src/Glpi/Asset/CustomFieldType/DateType.php
+++ b/src/Glpi/Asset/CustomFieldType/DateType.php
@@ -60,7 +60,7 @@ public function getFormInput(string $name, mixed $value, ?string $label = null,
 
     public function normalizeValue(mixed $value): ?string
     {
-        if ($value === null || $value === '') {
+        if (empty($value)) {
             return null;
         }
         if (!preg_match('/^\d{4}-\d{2}-\d{2}$/', $value)) {
@@ -71,7 +71,7 @@ public function normalizeValue(mixed $value): ?string
 
     public function formatValueFromDB(mixed $value): ?string
     {
-        if ($value === null) {
+        if (empty($value)) {
             return null;
         }
         return date('Y-m-d', strtotime($value . ' UTC'));