The Nikkei 225 Index rose 0.5% to above 40,800 while the broader Topix Index gained 0.3% to 2,930 on Thursday, recouping some losses from earlier in the week as investors prepared for the latest Bank of Japan monetary policy decision.
The BOJ is widely expected to leave interest rates unchanged as it evaluates the economic impact of US tariff actions.
However, the central bank is likely to raise its inflation forecast in its quarterly outlook amid persistent price pressures.
Investors also continued to monitor trade developments after the US reached new tariff agreements with India and South Korea.
Index heavyweights led the rally, with Disco up 3.7%, Fujikura 5.6%, Furukawa Electric 5.9%, Lasertec 2.8%, and SoftBank Group 1.8%.
AloJapan.com