Japan was China's third largest trading partner in 2005. According to customs statistics released in China, the bilateral trade volume between China and Japan in 2005 hit US$ 184.45 billion, up 9.9 percent over the previous year, among which China's exports to Japan accounted for US$ 83.99 billion, gaining 14.3 percent, while China's imports from Japan registered an increase of 6.5 percent to arrive at US$ 100.45 billion. China had a trade deficit of US$ 16.46 billion with Japan. China mainly exported to Japan electro-mechanic products, electrical appliances and electronic devices, garments and accessories, new and high-tech products, yarn and its products, clothing of woven fabric, fossil fuels, mineral oils, iron and steel, and metal materials. China's imports from Japan included, among others, electro-mechanic products, electrical appliances and electronic devices, new and high- tech products, electronic technology, diodes and analog semiconductor devices, integrated circuits and micro-electronic components, steel and its products, plastics and its products, and organic chemical products. The momentum of Sino-Japanese trade seemed to have slowed down in 2005, with the growth rate in bilateral trade falling behind the average growth in China's foreign trade.

As was released by China's Ministry of Commerce (MOFCOM), in 2005, the turnover of the completed engineering contracts by Chinese firms in Japan totaled US$ 100 million, and the volume of the newly signed engineering contracts reached US$ 110 million; the turnover of the completed labor service cooperation contracts stood at US$ 1,090 million, and the volume of the newly signed labor service contracts was worth US$ 1,190 million. All these figures indicate an increase, compared with last year. By the end of 2005, the accumulated turnover of the engineering contracts completed by Chinese companies in Japan added up to US$ 340 million, with that of the signed engineering contracts running into US$ 420 million; the accumulated volume of the completed labor service cooperation contracts amounted to US$ 5.27 billion, and that of the signed labor contracts came out at US$ 6.77 billion.

Upon the ratification or on the record of MOFCOM, 18 Chinese-funded non-financial enterprises were set up in Japan in 2005, with a contractual investment of US$ 12.46 million from the Chinese investors. By the end of 2005, a total number of 291 Chinese-invested non-financial companies had been established in Japan, with an overall contractual investment of US$ 1,180 million.

According to the figures of MOFCOM, Japanese firms invested in 3,269 projects in China in 2005, with a contractual investment of US$ 11.92 billion and an injected capital of US$ 6.53 billion. By the end of 2005, Japan had accumulatively invested in 35,124 projects in China, with a pledged investment of US$ 78.57 billion and an actual capital input of US$ 53.37 billion.