The benchmark Nikkei index at the Tokyo Stock Exchange fell 34.13 points to 9,443.04 by noon. The Topix index was off 0.14 percent, or 1.14 points, at 818.02.
The fall came as technology shares were dragged down by weakness in US tech stocks overnight, Kazuhiro Takahashi, general manager of investment strategy and research at Daiwa Securities, told Dow Jones Newswires.
"Broader trading will largely be confined to a narrow range today and the index may easily move in and out of negative territory," Takahashi said.
In the technology sector, Toshiba lost 2.77 percent to 420 yen and TDK was down 1.55 percent at 4,105 yen.
Sony dropped 1.89 percent to 2,227 yen, taking its cue from news on Tuesday that its websites in three countries had been hacked with 8,500 Greek user accounts compromised.
Carmakers were higher in the wake of media reports that Toyota is planning to bring its domestic production schedule forward.
Toyota rose 2.77 percent to 3,335 yen, Honda gained 1.32 percent to 3,065 yen and Nissan was up 1.53 percent at 793 yen.
There was little impact from data released shortly before the opening bell that showed Japan plunged into a trade deficit in April as exports tumbled 12.5 percent year-on-year due to supply chain disruptions after the March 11 earthquake and tsunami.
Japan logged a deficit of 463.7 billion yen ($5.6 billion) in April, reversing a year-before surplus of 729.2 billion yen. The deficit, however, was smaller than the market average forecast of 700 billion yen.
Investors had very low expectations and "any downside is already digested after last week's dismal GDP numbers", Takuya Yamada, senior portfolio manager at ITC Investment Partners, told Dow Jones.
Government data last week showed Japan's economy plunged back into recession in January-March, ravaged by the impact of the earthquake, tsunami and a subsequent nuclear crisis considered the worst since Chernobyl in 1986.
US stocks edged down Tuesday as two banks predicted oil prices would rise to $130 a barrel and data showed the market for new homes remained weak.
The Dow Jones Industrial Average fell 25.05 points (0.20 percent) to 12,356.21, while the tech-heavy Nasdaq Composite was 12.74 points (0.46 percent) lower at 2,746.16.
Copyright AFP (Agence France-Presse), 2011