diff --git a/src/shell/lua_repl.h b/src/shell/lua_repl.h
index bae05c749..8ddda8434 100644
--- a/src/shell/lua_repl.h
+++ b/src/shell/lua_repl.h
@@ -5,6 +5,8 @@ Released under Apache 2.0 license as described in the file LICENSE.
 Author: Leonardo de Moura
 */
 // Very simple read-eval-print for Lua
+
+#if LUA_VERSION_NUM >= 520
 static char const * g_lua_repl =
     "local function trim(s)\n"
     "   return s:gsub('^%s+', ''):gsub('%s+$', '')\n"
@@ -39,3 +41,39 @@ static char const * g_lua_repl =
     "        print(err)\n"
     "    end\n"
     "until false\n";
+#else /* For Lua 5.1, we  uses loadstring instead of load */
+static char const * g_lua_repl =
+    "local function trim(s)\n"
+    "   return s:gsub('^%s+', ''):gsub('%s+$', '')\n"
+    "end\n"
+    "local function show_results(...)\n"
+    "   if select('#', ...) > 1 then\n"
+    "      print(select(2, ...))\n"
+    "   end\n"
+    "end\n"
+    "print([[Type 'Exit' to exit.]])\n"
+    "repeat\n"
+    "    io.write'lean > '\n"
+    "    local s = io.read()\n"
+    "    if s == nil then print(""); break end\n"
+    "    if trim(s) == 'Exit' then break end\n"
+    "    local f, err = loadstring(s, 'stdin')\n"
+    "    if err then\n"
+    "        f = loadstring('return (' .. s .. ')', 'stdin')\n"
+    "    end\n"
+    "    if f then\n"
+    "        local ok, err = pcall(f)\n"
+    "        if not ok then\n"
+    "           if is_exception(err) then\n"
+    "               print(err:what())\n"
+    "           else\n"
+    "               print(err)\n"
+    "           end\n"
+    "        else\n"
+    "           if err then print(err) end\n"
+    "        end\n"
+    "    else\n"
+    "        print(err)\n"
+    "    end\n"
+    "until false\n";
+#endif