TOKYO, June 24 (Reuters) - Japan's Nikkei share average eked out gains on Monday after a mixed session on Wall Street last Friday, with export-related stocks getting some support from a weaker yen.

The S&P 500 and Nasdaq closed slightly lower on Friday while the Dow ended almost flat, with technical factors and a second day of declines for Nvidia weighing on the market.

"What we're seeing is a repeat of what happened into the end of May, where there was selling from these real money fund managers to get back to benchmark weightings, particularly things like the Nasdaq and Nvidia," said Tony Sycamore, a market analyst at IG.

That, in turn, weighs on the Nikkei, he added.

Japanese chip shares, in particular, which have been some of the Nikkei's strongest performers over the past year, were finding momentum hard to come by on Monday as a result.

The Nikkei rose 0.24% to 38,689.22 by the midday break. The broader Topix was up 0.26% at 2,731.69.

Export-related stocks advanced as the yen weakened towards the 160-per-dollar level. A weaker yen helps boost Japanese exporters' overseas earnings when repatriated and increases their competitiveness.

The Nikkei has traded in a narrow range in recent months, with the index on track for a less than 1% gain this month after a flat May.

"Since April, it's been in a period of consolidation," as investors wait out currency and bond market volatility and look for clarity from the Bank of Japan, IG's Sycamore said.

Among individual stocks, Toyota Motor rose 2.3% and was among the top percentage gainers on the Nikkei. Soy sauce maker Kikkoman and Chugai Pharmaceutical both climbed about 3%. SoftBank Group inched up 0.6%.

Online service platform operator Mercari was at the bottom with a 4.1% decline.

Among chip-related shares, Tokyo Electron edged down 0.1%, Disco Corp fell 0.8%, and Shin-Etsu Chemical slipped 0.1%. Advantest edged up 0.1%. (Reporting by Brigid Riley; Editing by Subhranshu Sahu)