Tokyo stocks fell 1.03 percent Thursday morning, hit by profit-taking after the biggest one-day percentage gain this year, while investors await the outcome of a central bank policy meeting.
The Nikkei 225 index lost 104.91 points to 10,055.49 by the break after surging 2.39 percent Wednesday to close above 10,000 for the first time in more than eight months.
The Topix index of all first-section issues was down 0.33 percent, or 2.77 points, at 836.57.
"The selling is thus far light compared with Wednesday's surge," Okasan Securities strategist Hideyuki Ishiguro told Dow Jones Newswires.
"Currency levels remain supportive, and players expect some kind of stock-friendly rhetoric from the central bank later today," he said. The Bank of Japan (BoJ) is to wrap up a two-day policy meeting Thursday.
Stocks had risen on the back of a weaker yen following a landslide win by the opposition Liberal Democratic Party and its ally in Japan's national elections on Sunday.
The BoJ is under scrutiny to see if its stance or rhetoric reflects an increase in pressure from the incoming coalition to further loosen monetary policy.
The yen was at 84.20 yen in Tokyo midday trade, compared with 84.39 yen in New York Wednesday afternoon. The euro bought 111.32 yen and $1.3219 against 111.59 yen and $1.3226 in US trade.
In trade in individual stocks, Mitsubishi Motors was down 6.59 percent to 85 yen after it widened a recall over an oil leak issue on vehicles sold in Japan to about 1.7 million units, prompting a rebuke by the transport ministry.
Mitsubishi Electric was up 2.41 percent to 762 yen, discounting a report in the Nikkei economic daily that the firm will pay 50 billion yen ($590 million) to Japan's defence ministry for overcharging for defence equipment.