In 1990, Mitsui first entered Indonesia as an independent power producer by establishing Paiton I, an electric steam power plant, followed by Paiton II in 2012 (in East Java). The company also established an ammonia plant (Kaltim Pacifik Ammoniak) that has been in operation since 2000, producing around 660 thousand ton of ammonia per year.

After China and Thailand, Indonesia is the third-largest investment destination for Japanese companies. The total value of investments and the number of projects have increased significantly in recent years. In 2010, Japanese companies invested a total of USD $712.5 million in Indonesia through 321 projects. Three years later (2013), the total value of investments had accelerated to USD $4.7 billion through a total of 950 projects, thus replacing Singapore as the largest foreign investor in Indonesia.

Iijima stated that some issues that should be dealt with by the Indonesian government include bureaucratic reforms, improving the country's infrastructure as well as curtailing corruption. If these issues are improved it will translate into rising investor confidence and more investments.

Japan's Investments in Indonesia:

Year  Number of Projects
 Value of Investment
2010               321         USD $0.71B
2011               421         USD $1.52B
2012               405         USD $2.45B
2013               950         USD $4.71B

Source: Indonesia Investment Coordinating Board