diff --git a/Changes b/Changes
index 4e1f71fe7..c988ff412 100644
--- a/Changes
+++ b/Changes
@@ -76,6 +76,7 @@ Verilator 5.037 devel
 * Fix `--lib-create` with double-underscore (#6099).
 * Fix DFG binToOneHot table index missing driver (#6100). [Geza Lore]
 * Fix decoding octal string escapes with 1-2 digits (#6108).
+* Fix colon-divide operator without space (#6121). [Alex Solomatnikov]
 
 
 Verilator 5.036 2025-04-27
diff --git a/src/verilog.l b/src/verilog.l
index 722ed6f3b..69ecd8d7a 100644
--- a/src/verilog.l
+++ b/src/verilog.l
@@ -647,9 +647,9 @@ vnum    {vnum1}|{vnum2}|{vnum3}|{vnum4}|{vnum5}
   /* Default PLI rule */
 <V95,V01NC,V01C,V05,VA5,S05,S09,S12,S17,S23,SAX>{
   "$"[a-zA-Z0-9_$]+     { const string str (yytext, yyleng);
-                                  yylval.strp = PARSEP->newString(AstNode::encodeName(str));
-                                  FL; return yaD_PLI;
-                                }
+                          yylval.strp = PARSEP->newString(AstNode::encodeName(str));
+                          FL; return yaD_PLI;
+                        }
 }
 
   /************************************************************************/
@@ -896,7 +896,7 @@ vnum    {vnum1}|{vnum2}|{vnum3}|{vnum4}|{vnum5}
   "@@"                  { FL; return yP_ATAT; }
   "::"                  { FL; return yP_COLONCOLON; }
   ":="                  { FL; return yP_COLONEQ; }
-  ":/"[^\/\*]           { FL; return yP_COLONDIV; }  /* : then comment is not ":/" */
+  ":/"/[^\/\*]          { FL; return yP_COLONDIV; }  /* : then comment is not ":/" */
   "|->"                 { FL; return yP_ORMINUSGT; }
   "|=>"                 { FL; return yP_OREQGT; }
   /* Some simulators allow whitespace here. Grr */
diff --git a/test_regress/t/t_constraint_dist.v b/test_regress/t/t_constraint_dist.v
index 343a7aad5..b138a3e33 100644
--- a/test_regress/t/t_constraint_dist.v
+++ b/test_regress/t/t_constraint_dist.v
@@ -28,7 +28,7 @@ class C;
    int arr[3] = '{5, 6, 7};
    constraint distrib {
       x dist { [1:3] := 0, [5:6], [9:15] :/ 0 };
-      y dist { [1:3] := 0, 5, 6 := 8, [9:15] :/ 0 };
+      y dist { [1:3] := 0, 5, 6 := 8, [9:15] :/0 };  // /0 intentional to check yP_COLONDIV
       x < 20;
    };
    constraint distinside {