A simple, efficient and cost effective method for the transesterification of structurally varied aromatic esters is described. Transesterification is carried out in presence of a highly active heterogeneous base catalyst developed from post-harvest banana plant. The catalyst derived from different parts of the post-harvest plant waste of the Musa balbisiana and Musa acuminata varieties of banana. Successful transesterification of a variety of esters have been achieved to the corresponding methyl esters using the catalyst at ambient temperature. The catalyst is renewable, cost-effective and non-polluting. Post-harvest banana has no commercial value and available at no cost. It has potential applications in biodiesel industries