This paper assesses the impact of environmental regulation in host countries on Japanese foreign direct investment (FDI) decision-making. It tests the pollution haven hypothesis using data on national environmental regulation standards and Japanese inward FDI in five dirty industries (iron and steel industry, non-ferrous metals industry, chemicals industry, paper and pulp industry, non-metallic products industry). The results do not support the pollution hypothesis. On the contrary, inward Japanese FDI appears to be attracted to countries which have committed themselves to a transparent and stable environment regulatory environment, suggesting that the quality of the regulatory framework in terms of its certainty and transparency has a greater influence on foreign investors' choice of location than the level of the environmental regulatory measures.