Tokyo stocks opened 0.67 percent higher on Monday after the yen fell against the dollar on confidence in the US economy.
The Nikkei 225 index at the Tokyo Stock Exchange was up 109.17 points to 16,339.03 at the start.
The yen was lower, a positive for Japanese exporters, helped by an upward revision to the second-quarter US economic growth estimate.
The dollar fetched 109.36 yen in early Monday trade, up from 109.28 yen in New York Friday afternoon and 108.92 yen in Tokyo earlier Friday.
The euro bought $1.2674 and 138.65 yen against $1.2683 and 138.60 yen in US trade.
Investors appeared to be largely discounting the financial impact of a deadly volcanic eruption in central Japan.
Shares in SoftBank rose 1.49 percent to 8,018.0 yen in the first few minutes of trade after media reports that the Japanese telecommunications group is in talks to buy DreamWorks Animation, the biggest independent animated film studio in Hollywood.
The deal could value DreamWorks at $3.4 billion, the Hollywood Reporter said.
US stocks Friday finished an up-and-down week on a high note, posting solid gains on a strong Nike earnings report and a rally in Apple shares.
The Dow Jones Industrial Average jumped 0.99 percent to 17,113.15, led by a 12.2 percent upsurge in Nike after announcing strong first-quarter earnings.