diff --git a/rtl/macos/macutils.inc b/rtl/macos/macutils.inc
index 4aa9db68be..9dce3fe289 100644
--- a/rtl/macos/macutils.inc
+++ b/rtl/macos/macutils.inc
@@ -144,9 +144,9 @@ end;
     {All kinds of paths are attempted to be translated, except the unusal }
     {dos construct: a relative path on a certain drive like : C:xxx\yyy}
 
-  function TranslatePathToMac (const path: string; mpw: Boolean): string;
+  function TranslatePathToMac (const path: shortstring; mpw: Boolean): Shortstring;
 
-    function GetVolumeIdentifier: string;
+    function GetVolumeIdentifier: Shortstring;
 
       var
         s: Str255;
@@ -269,7 +269,7 @@ end;
   end;
 
   {Concats the relative or full path path1 and the relative path path2.}
-  function ConcatMacPath (path1, path2: string): string;
+  function ConcatMacPath (path1, path2: Shortstring): Shortstring;
 
   begin
     if Pos(':', path1) = 0 then    {its partial}
@@ -295,7 +295,7 @@ end;
       end;
   end;
 
-  function IsMacFullPath (const path: string): Boolean;
+  function IsMacFullPath (const path: Shortstring): Boolean;
 
   begin
     if Pos(':', path) = 0 then    {its partial}
@@ -391,7 +391,7 @@ begin
   FSpGetFullPath := res;
 end;
 
-function PathArgToFSSpec(s: string; var spec: FSSpec): Integer;
+function PathArgToFSSpec(s: Shortstring; var spec: FSSpec): Integer;
 var
   err: OSErr;
 begin
@@ -406,7 +406,7 @@ begin
     PathArgToFSSpec := 3; {Empty paths are invalid paths}
 end;
 
-function PathArgToFullPath(s: string; var fullpath: RawByteString): Integer;
+function PathArgToFullPath(s: Shortstring; var fullpath: RawByteString): Integer;
 
 var
   err: OSErr;
@@ -424,7 +424,7 @@ begin
     PathArgToFullPath:=res;
 end;
 
-function GetVolumeName(vRefNum: Integer; var volName: String): OSErr;
+function GetVolumeName(vRefNum: Integer; var volName: ShortString): OSErr;
 
 var
   pb: HParamBlockRec;
diff --git a/rtl/macos/system.pp b/rtl/macos/system.pp
index a21ac55a5f..1404069ee0 100644
--- a/rtl/macos/system.pp
+++ b/rtl/macos/system.pp
@@ -230,7 +230,7 @@ begin
 end;
 
 { argument number l }
-function paramstr(l : longint) : string;
+function paramstr(l : longint) : shortstring;
 begin
   if (l>=0) and (l+1<=argc) then
     paramstr:=strpas(argv[l])