diff --git a/src/Psalm/Internal/Visitor/CheckTrivialExprVisitor.php b/src/Psalm/Internal/Visitor/CheckTrivialExprVisitor.php
index c9ce2fc631a..7a1f9319bf6 100644
--- a/src/Psalm/Internal/Visitor/CheckTrivialExprVisitor.php
+++ b/src/Psalm/Internal/Visitor/CheckTrivialExprVisitor.php
@@ -37,6 +37,7 @@ private function checkNonTrivialExpr(PhpParser\Node\Expr $node)
             || $node instanceof PhpParser\Node\Expr\Yield_
             || $node instanceof PhpParser\Node\Expr\YieldFrom
             || $node instanceof PhpParser\Node\Expr\New_
+            || $node instanceof PhpParser\Node\Expr\Cast\String_
         ) {
             if (($node instanceof PhpParser\Node\Expr\FuncCall
                     || $node instanceof PhpParser\Node\Expr\MethodCall
diff --git a/tests/FileManipulation/UnusedVariableManipulationTest.php b/tests/FileManipulation/UnusedVariableManipulationTest.php
index ac8acffb144..161e9334bec 100644
--- a/tests/FileManipulation/UnusedVariableManipulationTest.php
+++ b/tests/FileManipulation/UnusedVariableManipulationTest.php
@@ -587,6 +587,51 @@ function foo() : void {
                 ['UnusedVariable'],
                 true,
             ],
+            'dontRemoveUsedToStringCall' => [
+                '<?php
+                    class S {
+                        /**
+                         * @throws Exception
+                         */
+                        public function __toString() {
+                            if(rand(0,1)){
+                                throw new exception();
+                            }
+                            return "";
+                        }
+                    }
+
+                    function foo(S $a) {
+                        try {
+                            $b = (string) $a;
+                        } catch(Exception $e){
+                            // this class is not stringable
+                        }
+                    }',
+                '<?php
+                    class S {
+                        /**
+                         * @throws Exception
+                         */
+                        public function __toString() {
+                            if(rand(0,1)){
+                                throw new exception();
+                            }
+                            return "";
+                        }
+                    }
+
+                    function foo(S $a) {
+                        try {
+                            (string) $a;
+                        } catch(Exception $e){
+                            // this class is not stringable
+                        }
+                    }',
+                '7.1',
+                ['UnusedVariable'],
+                true,
+            ],
         ];
     }
 }