Tokyo stocks opened higher Wednesday following Wall Street's positive tone set overnight, while the yen's retreat against the U.S. dollar further lifted the market mood and gave exporters a boost.

As of 9:15 a.m., the 225-issue Nikkei Stock Average gained 146.59 points, or 0.73 percent, from Tuesday to 20,101.79.

The broader Topix index of all First Section issues on the Tokyo Stock Exchange, meanwhile, added 10.13 points, or 0.63 percent, to 1,627.20.

Nonferrous metal, machinery and securities-linked issues comprised those that gained the most in early trade.