diff --git a/config.xsd b/config.xsd
index 65fa59df7..6257eea10 100644
--- a/config.xsd
+++ b/config.xsd
@@ -137,6 +137,7 @@
             <xs:element name="InvalidScope" type="IssueHandlerType" minOccurs="0" />
             <xs:element name="InvalidStaticInvocation" type="IssueHandlerType" minOccurs="0" />
             <xs:element name="InvalidStaticVariable" type="IssueHandlerType" minOccurs="0" />
+            <xs:element name="InvalidStringClass" type="IssueHandlerType" minOccurs="0" />
             <xs:element name="InvalidThrow" type="IssueHandlerType" minOccurs="0" />
             <xs:element name="InvalidToString" type="IssueHandlerType" minOccurs="0" />
             <xs:element name="LessSpecificReturnStatement" type="IssueHandlerType" minOccurs="0" />
diff --git a/docs/issues.md b/docs/issues.md
index 5013446b5..7f2946b9a 100644
--- a/docs/issues.md
+++ b/docs/issues.md
@@ -340,6 +340,16 @@ class Foo {}
 (new foo());
 ```
 
+### InvalidStringClass
+
+Emitted when you have `allowStringToStandInForClass="false"` in your config and you’re passing a string instead of calling a class directly
+
+```php
+class Foo {}
+$a = "Foo";
+new $a();
+```
+
 ### InvalidClone
 
 Emitted when trying to clone a value that's not cloneable
diff --git a/src/Psalm/Checker/Statements/Expression/Call/NewChecker.php b/src/Psalm/Checker/Statements/Expression/Call/NewChecker.php
index 1313f8318..b9169cc6d 100644
--- a/src/Psalm/Checker/Statements/Expression/Call/NewChecker.php
+++ b/src/Psalm/Checker/Statements/Expression/Call/NewChecker.php
@@ -12,8 +12,9 @@ use Psalm\Context;
 use Psalm\Issue\AbstractInstantiation;
 use Psalm\Issue\DeprecatedClass;
 use Psalm\Issue\InterfaceInstantiation;
-use Psalm\Issue\InvalidClass;
+use Psalm\Issue\InvalidStringClass;
 use Psalm\Issue\TooManyArguments;
+use Psalm\Issue\UndefinedClass;
 use Psalm\IssueBuffer;
 use Psalm\Type;
 use Psalm\Type\Atomic\TNamedObject;
@@ -125,12 +126,26 @@ class NewChecker extends \Psalm\Checker\Statements\Expression\CallChecker
                         ) {
                             continue;
                         }
-                    } elseif ($lhs_type_part instanceof Type\Atomic\TMixed) {
+
+                        if (IssueBuffer::accepts(
+                            new InvalidStringClass(
+                                'String cannot be used as a class',
+                                new CodeLocation($statements_checker->getSource(), $stmt)
+                            ),
+                            $statements_checker->getSuppressedIssues()
+                        )) {
+                            // fall through
+                        }
+
+                        continue;
+                    }
+
+                    if ($lhs_type_part instanceof Type\Atomic\TMixed) {
                         continue;
                     }
 
                     if (IssueBuffer::accepts(
-                        new InvalidClass(
+                        new UndefinedClass(
                             'Type ' . $lhs_type_part . ' cannot be called as a class',
                             new CodeLocation($statements_checker->getSource(), $stmt)
                         ),
diff --git a/src/Psalm/Checker/Statements/Expression/Call/StaticCallChecker.php b/src/Psalm/Checker/Statements/Expression/Call/StaticCallChecker.php
index 2a21cfa95..ada9485d9 100644
--- a/src/Psalm/Checker/Statements/Expression/Call/StaticCallChecker.php
+++ b/src/Psalm/Checker/Statements/Expression/Call/StaticCallChecker.php
@@ -11,8 +11,9 @@ use Psalm\Config;
 use Psalm\Context;
 use Psalm\FileManipulation\FileManipulationBuffer;
 use Psalm\Issue\DeprecatedClass;
-use Psalm\Issue\InvalidClass;
+use Psalm\Issue\InvalidStringClass;
 use Psalm\Issue\ParentNotFound;
+use Psalm\Issue\UndefinedClass;
 use Psalm\IssueBuffer;
 use Psalm\Type;
 use Psalm\Type\Atomic\TNamedObject;
@@ -205,12 +206,26 @@ class StaticCallChecker extends \Psalm\Checker\Statements\Expression\CallChecker
                     ) {
                         continue;
                     }
-                } elseif ($lhs_type_part instanceof Type\Atomic\TMixed) {
+
+                    if (IssueBuffer::accepts(
+                        new InvalidStringClass(
+                            'String cannot be used as a class',
+                            new CodeLocation($statements_checker->getSource(), $stmt)
+                        ),
+                        $statements_checker->getSuppressedIssues()
+                    )) {
+                        // fall through
+                    }
+
+                    continue;
+                }
+
+                if ($lhs_type_part instanceof Type\Atomic\TMixed) {
                     continue;
                 }
 
                 if (IssueBuffer::accepts(
-                    new InvalidClass(
+                    new UndefinedClass(
                         'Type ' . $lhs_type_part . ' cannot be called as a class',
                         new CodeLocation($statements_checker->getSource(), $stmt)
                     ),
diff --git a/src/Psalm/Issue/InvalidStringClass.php b/src/Psalm/Issue/InvalidStringClass.php
new file mode 100644
index 000000000..2e2a1fb4c
--- /dev/null
+++ b/src/Psalm/Issue/InvalidStringClass.php
@@ -0,0 +1,6 @@
+<?php
+namespace Psalm\Issue;
+
+class InvalidStringClass extends CodeIssue
+{
+}
diff --git a/tests/AnnotationTest.php b/tests/AnnotationTest.php
index 1959e66e4..cd17ef825 100644
--- a/tests/AnnotationTest.php
+++ b/tests/AnnotationTest.php
@@ -133,7 +133,7 @@ class AnnotationTest extends TestCase
 
     /**
      * @expectedException        \Psalm\Exception\CodeException
-     * @expectedExceptionMessage InvalidClass
+     * @expectedExceptionMessage InvalidStringClass
      *
      * @return                   void
      */
@@ -156,7 +156,7 @@ class AnnotationTest extends TestCase
 
     /**
      * @expectedException        \Psalm\Exception\CodeException
-     * @expectedExceptionMessage InvalidClass
+     * @expectedExceptionMessage InvalidStringClass
      *
      * @return                   void
      */
diff --git a/tests/DocumentationTest.php b/tests/DocumentationTest.php
index fbf4a924b..960093a7a 100644
--- a/tests/DocumentationTest.php
+++ b/tests/DocumentationTest.php
@@ -148,6 +148,9 @@ class DocumentationTest extends TestCase
 
         foreach (self::getCodeBlocksFromDocs() as $issue_name => $blocks) {
             switch ($issue_name) {
+                case 'InvalidStringClass':
+                    continue 2;
+
                 case 'InvalidFalsableReturnType':
                     $ignored_issues = ['FalsableReturnStatement'];
                     break;
diff --git a/tests/MethodCallTest.php b/tests/MethodCallTest.php
index 56c724434..bbf7bcc00 100644
--- a/tests/MethodCallTest.php
+++ b/tests/MethodCallTest.php
@@ -271,13 +271,13 @@ class MethodCallTest extends TestCase
                 '<?php
                     $a = 5;
                     $a::bar();',
-                'error_message' => 'InvalidClass',
+                'error_message' => 'UndefinedClass',
             ],
             'intVarNewCall' => [
                 '<?php
                     $a = 5;
                     new $a();',
-                'error_message' => 'InvalidClass',
+                'error_message' => 'UndefinedClass',
             ],
         ];
     }