diff --git a/components/chemtext/source/chemtext.pas b/components/chemtext/source/chemtext.pas
index 624f0a756..e57d59df2 100644
--- a/components/chemtext/source/chemtext.pas
+++ b/components/chemtext/source/chemtext.pas
@@ -133,7 +133,7 @@ implementation
 {$R chemtext.res}
 
 uses
-  Themes, Math;
+  Themes, Math, LazUtf8;
 
 type
   TArrowDir = (adLeft, adRight, adBoth);
@@ -251,7 +251,7 @@ var
 
 var
   x0: Integer;
-  i, j: integer;
+  i, j, n: integer;
   s: string;
   subNos: boolean;        // "subscript numbers"
   escaping: Boolean;
@@ -349,14 +349,16 @@ begin
 
           SUPERSCRIPT_CHAR:
             begin
-              inc(i);
-              DrawSup(X, Y, AText[i]);
+              n := UTF8CodePointSize(@AText[i+1]);
+              DrawSup(X, Y, copy(AText, i+1, n));
+              inc(i, n);
             end;
 
           SUBSCRIPT_CHAR:
             begin
-              inc(i);
-              DrawSub(X, Y, AText[i]);
+              n := UTF8CodePointSize(@AText[i+1]);
+              DrawSub(X, Y, copy(AText, i+1, n));
+              inc(i, n);
             end;
 
           else