TOKYO — Japan’s Nikkei 225 stock index closed Thursday at a fresh record high of 40,913.65, pushing past its most recent record close set in March on heavy buying of automaker and technology shares.

The index gained 0.8%, buoyed by heavy buying of technology and export-oriented shares. The index’s all-time high during intraday trading is 41,087.75, set on March 22. Its previous record close was 40,888.43, also set on March 22.

The gains tracked an overnight rally on Wall Street, where the S&P 500 and tech-heavy Nasdaq also hit fresh records.

Both foreign and domestic investors have piled into the Japanese market in recent months even as the economy has slowed. Part of the attraction is the weakness of the Japanese yen, which is trading at 34-year lows against the dollar. A weak yen tends to push the dollar-denominated overseas profits of exporters higher when they are repatriated to Japan.

But changes to investment regulations have also lured many Japanese investors into the equity market. As of this year, so-called NISA, or Nippon (Japan) Individual Savings Accounts, became tax-free investment options, with limits raised for how much can be kept in such accounts and for how long.

Among big gainers on Thursday, Mitsubishi Heavy Industries advanced 3.8%; Nissan Motor Co. added 4.5% and Toyota Motor Corp. was up 2%. Computer chip testing equipment maker Advantest jumped 2.1%.

The Nikkei 225 index has gained 22.4% so far this year. It surged in the late 1980s during Japan’s bubble economy, when asset prices soared. But it collapsed when that financial bubble imploded in early 1990, after hitting its earlier record of 38,915.87 at the end of 1989.