Fatty Acid Methyl Ester (FAME) is renewable biodiesel which can be produced from transesterification/esterification reaction of palm oil with alcohol as an alternative for diminishing fossil fuel. This reaction required strong acid catalyst. In this study, the synthesis of FAME from palm oil using sulfated titanium dioxide (TiO2) nanowires as catalyst has been carried out successfully. The sulfated TiO2 nanowires were synthesized using hydrothermal method (denoted as S-TNWH) and molten salt method (denoted as S-TNWMS). Both catalysts were utilized in the esterification reaction of palm oil with methanol to produce FAME. GCMS analysis of the product showed that both catalysts showed good catalytic activity with 100% selectivity to FAME. However, the conversion S-TNWMS (94%) was higher compared to S-TNWH (89%) catalyst. The molten salt method offers a simple and environmentally friendly method to produce catalyst with high catalytic activity. © 2026 American Institute of Physics Inc.. All rights reserved.