diff --git a/compiler/frontend/src/org/jetbrains/jet/lang/resolve/lazy/descriptors/LazyClassMemberScope.java b/compiler/frontend/src/org/jetbrains/jet/lang/resolve/lazy/descriptors/LazyClassMemberScope.java
index 54f77f7a0f2..2b23821ec36 100644
--- a/compiler/frontend/src/org/jetbrains/jet/lang/resolve/lazy/descriptors/LazyClassMemberScope.java
+++ b/compiler/frontend/src/org/jetbrains/jet/lang/resolve/lazy/descriptors/LazyClassMemberScope.java
@@ -190,9 +190,13 @@ public class LazyClassMemberScope extends AbstractLazyMemberScope<LazyClassDescr
         }
 
         if (name.equals(DescriptorResolver.COPY_METHOD_NAME)) {
-            SimpleFunctionDescriptor copyFunctionDescriptor = DescriptorResolver.createCopyFunctionDescriptor(
-                    constructor.getValueParameters(),
-                    thisDescriptor, trace);
+            for (ValueParameterDescriptor parameter : constructor.getValueParameters()) {
+                // force properties resolution to fill BindingContext.VALUE_PARAMETER_AS_PROPERTY slice
+                getProperties(parameter.getName());
+            }
+
+            SimpleFunctionDescriptor copyFunctionDescriptor =
+                    DescriptorResolver.createCopyFunctionDescriptor(constructor.getValueParameters(), thisDescriptor, trace);
             result.add(copyFunctionDescriptor);
         }
     }
diff --git a/idea/testData/multiFileHighlighting/copyResolveBeforeParams.kt b/idea/testData/multiFileHighlighting/copyResolveBeforeParams.kt
new file mode 100644
index 00000000000..e733badbf4e
--- /dev/null
+++ b/idea/testData/multiFileHighlighting/copyResolveBeforeParams.kt
@@ -0,0 +1,11 @@
+package copytest
+
+import dataclass.Settings
+
+fun foo(s: Settings) {
+    s.copy(1, 32)
+    s.copy(1)
+}
+
+// KT-5975 data class copy method invocation gives errors in IDE when some optional parameters specified
+/* Resolution of copy was called before parameters resolve */
\ No newline at end of file
diff --git a/idea/testData/multiFileHighlighting/dependencies/dataClass.kt b/idea/testData/multiFileHighlighting/dependencies/dataClass.kt
new file mode 100644
index 00000000000..1f55ecfb06f
--- /dev/null
+++ b/idea/testData/multiFileHighlighting/dependencies/dataClass.kt
@@ -0,0 +1,3 @@
+package dataclass
+
+data class Settings(b: Int = 1, val a: Int)
\ No newline at end of file
diff --git a/idea/tests/org/jetbrains/jet/plugin/stubs/MultiFileHighlightingTestGenerated.java b/idea/tests/org/jetbrains/jet/plugin/stubs/MultiFileHighlightingTestGenerated.java
index 701a5552609..8eef440c7b3 100644
--- a/idea/tests/org/jetbrains/jet/plugin/stubs/MultiFileHighlightingTestGenerated.java
+++ b/idea/tests/org/jetbrains/jet/plugin/stubs/MultiFileHighlightingTestGenerated.java
@@ -38,6 +38,12 @@ public class MultiFileHighlightingTestGenerated extends AbstractMultiFileHighlig
         JetTestUtils.assertAllTestsPresentByMetadata(this.getClass(), new File("idea/testData/multiFileHighlighting"), Pattern.compile("^(.+)\\.kt$"), false);
     }
     
+    @TestMetadata("copyResolveBeforeParams.kt")
+    public void testCopyResolveBeforeParams() throws Exception {
+        String fileName = JetTestUtils.navigationMetadata("idea/testData/multiFileHighlighting/copyResolveBeforeParams.kt");
+        doTest(fileName);
+    }
+    
     @TestMetadata("delegatesReference.kt")
     public void testDelegatesReference() throws Exception {
         String fileName = JetTestUtils.navigationMetadata("idea/testData/multiFileHighlighting/delegatesReference.kt");