The Nikkei 225 started the day on a high note and, for the first time, reached the record level of 68,000 points. At lunchtime, the main index was up 2.6 percent. The broader Topix was up 1.8 percent.
In China, Shenzhen rose 1.9 percent and Shanghai was slightly lower at 0.2 percent.
However, the Hong Kong-based Hang Seng bucked the upward trend and fell 1.5 percent.
South Korea's Kospi was closed for the weekend.
