
The Nikkei jumped 2.8%, or 1,162.86 points, to 42,983.34 in the afternoon before easing back slightly.
The previous record was 42,426.77, set in July last year.
IwaiCosmo Securities said in a market commentary that “easing tensions over US-China trade talks, as well as speculation about the US’s imminent lowering of (interest) rates” had helped boost investors’ hopes about the recovery of Japanese companies.
That was leading to continued buying, it added.
A broad range of shares continued to surge shortly after the midday break.
Following gains in US tech shares, Japanese tech investor SoftBank group jumped 7.07% to ¥14,845 and Advantest, maker of semiconductor tests, rose 7.34% to ¥11,255.
Automaker Toyota added 3.14% to ¥ 2,860 and Uniqlo-operator Fast Retailing added 4.67% to ¥ 48,440.