Tokyo's Nikkei stock index posted its largest gain this year and ended at a new nine-month high Wednesday.
The index was lifted by strong advances in banking and export-oriented technology issues on overnight rises in U.S. shares and hopes for an economic recovery in Japan.
The 225-issue Nikkei stock average jumped 313.75 points, or 3.38 percent, to close at an intraday high of 9,592.24, its highest closing since last Sept. 19.
The broader Tokyo Stock Price Index of all first section issues on the Tokyo Stock Exchange climbed 28.98 points, or 3.16 percent, to 945.24. The jump marked its highest finish so far this year.
The key Nikkei index chased higher ground following a more than 2 percent gain the previous day, as improved sentiment about Japan's economy prompted more buying in a wide range of issues, brokers said.
"Adding to hopes for improvement in corporate earnings, sentiment about the nation's economic fundamentals also seems to have begun improving," said Hiroshi Sato, equity general manager at Cosmo Securities Co. "The recent surge in stock itself also became a supporting factor for buying stocks, by making investor sentiment bullish."
Finance Minister Masajuro Shiokawa said he thinks the surge reflects an improved outlook by businesses.
"One reason is the brightness in the corporate sector," Shiokawa said at a press conference when asked to explain the rise in stock prices. Japan's four major banking groups all gained ground as recent firmness in Japanese stocks erased worries about possible appraisal losses due to bond price falls, brokers said.
Trading was heavy, with volume on the TSE's main section increasing to 1.931 billion shares from Tuesday's 1.778 billion. It was the 25th straight session, the longest streak ever, in which share trading eclipsed 1 billion.
Advancing issues overwhelmed decliners 1,091 to 355, with 80 issues closing unchanged.