Chinese non-financial investment in Japan declined 9.1 percent year-on-year in the first half of this year, Shen Danyang, spokesman for the Ministry of Commerce, told a news briefing on Wednesday.

In contrast, Japanese spending in China's non-financial sectors rose 14.37 percent year-on-year to $4.69 billion in the same period, according to the ministry.

China kept improving its investment environment while transnational companies are optimistic about China's economic outlook, Shen said.

But Japan's economic performance and its investment environment disappointed Chinese investors who are swarming for overseas investment.

Chinese investors complained about barriers in developed economies, including Japan, while Chinese policies are welcome foreign investments, Shen said.