Papua New Guinea（PNG）is the largest Pacific island country with a rich endowment of minerals and energy resources such as gold，copper，oil and natural gas. The PNG government has increased its efforts to attract foreign investment and made substantial progress such as in the Ramu Nickle and LNG projects. PNG is China’s most important trading partner and investment destination in the South Pacific. For instance，the Ramu Nickle project is China’s largest investment project in the region. In 2009，Sinopec entered into the agreement with Exxon Mobil to purchase PNG LNG. The gas supply has started since the end of 2014. In recent years，Chinese companies have also made breakthrough in winning project contracts in PNG，covering a wide range of sectors including roads，ports，house construction and telecommunications. However，the investment environment in PNG is complicated which is featured by complex cultural and ethnic factors，weak governance of the government，polarization of rich and poor，and the exacerbation of social security. This has put foreign investors including Chinese companies at great risks. As research on this topic from Chinese scholars in limited，this paper aims to fill the gap. Building upon the literature and the author’s recent fieldwork in PNG，the paper will provide an overview of the investment environment in PNG and explore its main features. It will also examine opportunities and challenges faced by Chinese companies. Brief policy suggestions will also be provided in the conclusion.