Tokyo stocks opened 0.70 percent higher on Wednesday after Wall Street shares soared on the new US Federal Reserve chair's promise of continuity in the central bank's monetary policy.
The Nikkei-225 index rose 103.39 points to 14,821.73 at the start.
It came after the Dow Jones Industrial Average leaped 1.22 percent to 15,994.77 on Tuesday as stocks reacted warmly to remarks by new US Federal Reserve chair Janet Yellen.
"Yellen hit just the right note with the market, reassuring that there would be no major break with the existing policy, while remaining somewhat cautious," said SMBC Nikko Securities general manager of equities Hiroichi Nishi.
"How emerging markets handle ongoing US tapering is another matter, but for now the net impact on Japan shares should be positive."
In her first public comments on policy since becoming Fed chair at the beginning of this month, Yellen told Congress on Tuesday that the US economy was expected to grow this year and next at a moderate pace, despite some recent poor data.
That would keep the Fed on course to slowly taper its currently $65-billion-a-month stimulus programme, a plan which has already driven interest rates higher and added to turmoil in emerging markets.
She allowed that when the Federal Open Market Committee, the Fed's policy-making body, meets next in March, it could weigh a pause to the taper if economic conditions show a significant deterioration.
"I expect a great deal of continuity in the FOMC's approach to monetary policy," she told the Financial Services Committee of the US House of Representatives.
The dollar got support from Yellen's comment, trading at 102.53 yen early Wednesday compared with 102.64 yen in New York Tuesday afternoon.
The euro bought $1.3636 and 139.85 yen against $1.3638 and 139.99 yen yen.
-- Dow Jones Newswires contributed to this article --