Japan's Nikkei share average dropped 0.8% on Wednesday to mark its seventh consecutive session of losses as fresh concerns about Spanish and Italian finances and slowing global growth sapped investor appetite.
Sony Corp and Sharp Corp's forecast of bigger annual losses and a firmer yen also weighed on Japanese electronics companies.
The Nikkei was down 79.28 points at 9,458.74, extending its worst run since July 2009.
Sony tumbled 4.5% after the consumer electronics company forecast a record $6.4 billion annual net loss on Tuesday, doubling an earlier forecast and marking a fourth consecutive year in the red.
Toshiyuki Kanayama, a senior market analyst at Monex Inc, said Sony's steep losses were unlikely to continue into Thursday, but the core problem faced by the company remains.
"The issue is that they don't have any new products to move forward with," he said, adding that Panasonic Corp and Sharp suffer from a similar problem.
Sharp shed 3.2% after it raised its overall loss forecast for the year that ended March to a record net deficit of 380 billion yen, a 31% increase from an earlier estimate.
"Japan's consumer electronics industry is facing defeat," said Fujio Ando, senior managing director of Chibagin Asset Management.
A stronger yen, with the dollar last traded at 80.897 yen, diminished investor appetite for Tokyo stocks, with major exporters sold heavily. Toyota Motor Corp, Honda Motor Co and Panasonic fell between 1.2 and 2.2%.
Monex's Kanayama said the next psychologically key level would be around 9,200, edging towards its 200-day moving average at 9,093. The index has lost 6.2% so far in April after rising more than 19% in the January-March period.
The broader Topix index lost 0.9% to finish at 805.84.
Nearly 2.1 billion shares changed hands on the main board, up from 1.93 billion shares on Tuesday.
Europe peripherals
"The problem is Europe ... we have been worried about Greece and have largely overlooked the problems in Italy, Spain and European peripherals," said Yutaka Miura, senior technical analyst at Mizuho Securities.
European shares slid on Tuesday after yields on Spanish and Italian debt rose, as doubts over global growth exacerbated concerns about the fragility of peripheral euro zone economies.
Adding to these concerns, Spain's central bank governor warned that the country's banks may need more capital if the economy deteriorates.
Most market participants remained optimistic that the Bank of Japan will take additional accommodative measures and give Tokyo equities a boost at its meeting later this month after it refrained from action at Tuesday's meeting.
However, HSBC was sceptical that the BOJ had become serious about quantitative easing and remained "underweight" on Japanese equities.
"We are unconvinced it is serious about achieving its inflation 'target'. One sign of this is that the Japanese word it uses, medo, means a vague aim or outlook and is not the conventional word for target (mokuhyo)," said Garry Evans, HSBC's global head of equity strategy, in a report.
Evans said BOJ chief Masaaki Shirakawa's remarks at a Fed conference on March 24 was further evidence of its reluctance to act.
"He (Shirakawa) argued that excessive monetary easing after a crisis is likely to backfire because it will tend to reduce incentives to cut debt, negatively affect productivity, hurt bank profits and push up commodity prices."
