Tokyo's key Nikkei index opened higher Wednesday extending rallies on Wall Street as fears ebbed that the virus outbreak in China would cause global economic disruption.
The Nikkei 225 index edged up 0.28 percent, or 66.14 points, to 23,752.12 in early trade, while the broader Topix index was down 0.05 percent, or 0.92 points, at 1,718.72.
"Japanese shares are testing the upside following sound US stocks trade," Yoshihiro Ito, chief strategist at Okasan Online Securities, said in a commentary.
Concerns over risks linked to the new coronavirus are "receding after Chinese shares showed resilience," he added.
The dollar fetched 109.83 yen in early Asian trade, against 109.78 yen in New York.
In Tokyo, SoftBank Group surged 11.34 percent to 5,723 yen after news in the US of approval of the T-Mobile and Sprint merger -- more than two years after it was first announced.
The merger reduces the risk that SoftBank will need to fund its unit Sprint, which will help improve the parent firm's balance sheet, analysts said.
Some exporters were higher, with semiconductor-making equipment maker Tokyo Electron advancing 2.69 percent to 24,980 yen and electronic components maker Murata Manufacturing trading up 1.43 percent at 6,585 yen.
Pharmaceuticals were mixed, with Takeda Pharmaceutical rallying 0.78 percent to 4,398 yen, Daiichi Sankyo trading down 0.54 percent at 8,032 yen and Shionogi off 2.65 percent at 6,519 yen.
On Wall Street, the broad-based S&P 500 and the tech-rich Nasdaq both hit records, albeit just a few tenths of a percentage point over their previous peaks, while the Dow Jones Industrial Average finished flat at 29,276.34.