The benchmark index for the Tokyo Stock Exchange hit an all-time intraday high on Friday, led by semiconductor-related shares. It broke the previous record, set about three months ago.
The Nikkei 225 rose to the 41,100 level, hitting the intraday high soon after opening.
Analysts say investors placed buy orders for semiconductor-related issues on expectations of strong corporate performance amid the weak yen.
But it finished the day at 40,912, down 1 point. Profit taking by some investors ended a five-day winning streak.