diff --git a/src/PhpSpreadsheet/Calculation/Functions.php b/src/PhpSpreadsheet/Calculation/Functions.php
index 0ec396f6e3..a645d790a4 100644
--- a/src/PhpSpreadsheet/Calculation/Functions.php
+++ b/src/PhpSpreadsheet/Calculation/Functions.php
@@ -153,7 +153,7 @@ public static function ifCondition($condition): string
     {
         $condition = self::flattenSingleValue($condition);
 
-        if ($condition === '') {
+        if ($condition === '' || $condition === null) {
             return '=""';
         }
         if (!is_string($condition) || !in_array($condition[0], ['>', '<', '='], true)) {
diff --git a/tests/PhpSpreadsheetTests/Reader/Xlsx/Issue3613Test.php b/tests/PhpSpreadsheetTests/Reader/Xlsx/Issue3613Test.php
new file mode 100644
index 0000000000..71899039e4
--- /dev/null
+++ b/tests/PhpSpreadsheetTests/Reader/Xlsx/Issue3613Test.php
@@ -0,0 +1,25 @@
+<?php
+
+namespace PhpOffice\PhpSpreadsheetTests\Reader\Xlsx;
+
+use PhpOffice\PhpSpreadsheet\Reader\Xlsx;
+use PhpOffice\PhpSpreadsheetTests\Functional\AbstractFunctional;
+
+class Issue3613Test extends AbstractFunctional
+{
+    private static string $testbook = 'tests/data/Reader/XLSX/issue.3613.xlsx';
+
+    // Partial fix only. We will no longer throw exception on save.
+    // But calculation for cell value is 0, which is incorrect.
+    public function testIssue3613(): void
+    {
+        $reader = new Xlsx();
+        $spreadsheet = $reader->load(self::$testbook);
+        $reloadedSpreadsheet = $this->writeAndReload($spreadsheet, 'Xlsx');
+        $spreadsheet->disconnectWorksheets();
+        $sheet = $reloadedSpreadsheet->getActiveSheet();
+        self::assertSame('=ROUND(MAX((O4-P4)*{0.03;0.1;0.2;0.25;0.3;0.35;0.45}-{0;2520;16920;31920;52920;85920;181920},0)-Q4,2)', $sheet->getCell('N4')->getValue());
+
+        $reloadedSpreadsheet->disconnectWorksheets();
+    }
+}
diff --git a/tests/data/Reader/XLSX/issue.3613.xlsx b/tests/data/Reader/XLSX/issue.3613.xlsx
new file mode 100644
index 0000000000..4b1296fee7
Binary files /dev/null and b/tests/data/Reader/XLSX/issue.3613.xlsx differ