diff --git a/packages/fcl-passrc/src/pastree.pp b/packages/fcl-passrc/src/pastree.pp
index 2e2e316069..d4cff7f5e4 100644
--- a/packages/fcl-passrc/src/pastree.pp
+++ b/packages/fcl-passrc/src/pastree.pp
@@ -794,7 +794,7 @@ type
   public
     PackMode: TPackMode;
     Members: TFPList;
-    RTTIVisibility: TRTTIVisibility;
+    RTTIVisibility: TRTTIVisibility; // set by $RTTI directive
     Constructor Create(const AName: TPasTreeString; AParent: TPasElement); override;
     Destructor Destroy; override;
     procedure FreeChildren(Prepare: boolean); override;
diff --git a/packages/pastojs/src/fppas2js.pp b/packages/pastojs/src/fppas2js.pp
index 8d3d02e1ab..30c753ca6c 100644
--- a/packages/pastojs/src/fppas2js.pp
+++ b/packages/pastojs/src/fppas2js.pp
@@ -567,6 +567,8 @@ const
   ExtRTTIVisPublic = 2;
   ExtRTTIVisPublished = 3;
   ExtRTTIVisPublicPublished = 4; // in source published, in RTTI public
+  ExtRTTIVisStrictPrivate = 5;
+  ExtRTTIVisStrictProtected = 6;
   ExtRTTIVisDefaultField = ExtRTTIVisPublic;
   ExtRTTIVisDefaultMethod = ExtRTTIVisPublic;
   ExtRTTIVisDefaultProperty = ExtRTTIVisPublicPublished;
@@ -20762,8 +20764,16 @@ var
 begin
   ExtVis:=TPasMembersType.VisibilityToExtRTTI[El.Visibility];
   case ExtVis of
-    vcPrivate: Result:=ExtRTTIVisPrivate;
-    vcProtected: Result:=ExtRTTIVisProtected;
+    vcPrivate:
+      if El.Visibility=visStrictPrivate then
+        Result:=ExtRTTIVisStrictPrivate
+      else
+        Result:=ExtRTTIVisPrivate;
+    vcProtected:
+      if El.Visibility=visStrictProtected then
+        Result:=ExtRTTIVisStrictProtected
+      else
+        Result:=ExtRTTIVisProtected;
     vcPublic: Result:=ExtRTTIVisPublic;
     vcPublished:
       if not (vcPublished in Vis) then
diff --git a/packages/pastojs/tests/tcmodules.pas b/packages/pastojs/tests/tcmodules.pas
index acd2c5de54..29ef892791 100644
--- a/packages/pastojs/tests/tcmodules.pas
+++ b/packages/pastojs/tests/tcmodules.pas
@@ -31726,10 +31726,14 @@ begin
   Add('type');
   Add('{$RTTI explicit fields([vcPrivate,vcProtected,vcPublic,vcPublished])}');
   Add('  TObject = class');
+  Add('  strict private');
+  Add('    A1: word;');
   Add('  private');
-  Add('    A: word;');
+  Add('    A2: word;');
+  Add('  strict protected');
+  Add('    B1: word;');
   Add('  protected');
-  Add('    B1, B2: word;');
+  Add('    B2, B3: word;');
   Add('  public');
   Add('    C: word;');
   Add('  published');
@@ -31741,18 +31745,22 @@ begin
     LinesToStr([ // statements
     'rtl.createClass(this, "TObject", null, function () {',
     '  this.$init = function () {',
-    '    this.A = 0;',
+    '    this.A1 = 0;',
+    '    this.A2 = 0;',
     '    this.B1 = 0;',
     '    this.B2 = 0;',
+    '    this.B3 = 0;',
     '    this.C = 0;',
     '    this.D = 0;',
     '  };',
     '  this.$final = function () {',
     '  };',
     '  var $r = this.$rtti;',
-    '  $r.addField("A", rtl.word, 0);',
-    '  $r.addField("B1", rtl.word, 1);',
+    '  $r.addField("A1", rtl.word, 5);',
+    '  $r.addField("A2", rtl.word, 0);',
+    '  $r.addField("B1", rtl.word, 6);',
     '  $r.addField("B2", rtl.word, 1);',
+    '  $r.addField("B3", rtl.word, 1);',
     '  $r.addField("C", rtl.word);',
     '  $r.addField("D", rtl.word, 3);',
     '});',