Pongamia pinnata (L.) Pierre is a fast-growing, leguminous and multipurpose tree species. It grows on degraded and marginal land in South and Southeast Asia. It produces non-edible seeds, the oil of which is a potential biofuel. In Indonesia, pongamia is widely found on all islands, but mostly to the west of the Wallace Line, in Banten, East Java, South Sumatra and West Java provinces. The economic viability of pongamia depends on the number of seeds per tree and the oil content of seeds. Studies on pongamia in Indonesia, with oil extracted using a simple mechanical expeller press, revealed that trees growing in Ujung Kulon National Park in Banten Province produce seeds with a higher oil content (15.59%) than those growing in the provinces of East and West Java. In this study, the oil content of 48 individual trees from Ujung Kulon National Park were analysed using a solvent extraction method. As a control, bulk seed was extracted using two different methods: 1) a Fabricant mechanical screw expeller press; and 2) solvent extraction. The results showed highly significant variance in oil content. Oil production of individual trees processed using the solvent extraction method reached 44% (varying from 26.61% to 44.68%), substantially higher than those using mechanical pressing at only 15% to 19%. Findings show that genetic factors, extraction machines and method of extraction can all influence pongamia oil production. The quality and genetic diversity of the seed source is also extremely important for industrial plantation forest programmes for bioenergy and land restoration in Indonesia.