Catalysts play vital role in the conversion of FFA or feed stocks to respective esters at faster rate and in minimum reaction temperature. Different research groups have produced biodiesel through transesterification using methanol or ethanol along with catalysts of different kinds. These catalysts have been identified as homogenous and heterogeneous catalysts. Among these catalysts, homogeneous catalysts have been preferred by many researchers for the reason that more biodiesel can be produced relatively at faster rate. These homogeneous catalysts are available both in liquid and solid form at ambient conditions. On the basis of their physical and chemical properties and their ability to reactivity, the catalyst in liquid or solid phase is selected for either esterification or transesterification. This paper provides information on the homogeneous catalysts and their properties. Use of homogeneous catalysts by different research groups has also been reviewed.