Abstract The study investigates biodiesel synthesis from waste seeds derived Mesua ferrea oil (MFO) using indigenously developed biocatalyst via lipase immobilisation on coconut shells derived microporous activated carbon (AC). The carbonaceous support was developed through steam activation of carbonised char at optimised activation conditions to attain maximum porous properties. The hydrolytic enzyme i.e. lipase was immobilised on prepared AC through adsorption process at different functional variables. The enzyme loading or uptake of carbonaceous support and enzymatic activity of respective sample at each set of parametric conditions were estimated. The adsorption assisted immobilisation was optimised employing Taguchi method and significant factors affecting highly both the responses were identified through estimation of statistical constraints. The optimised conditions derived using 3FI model were: Initial protein concentration 500 mg/L, time 270 min, temperature 15 °C, and solution pH 6 for achieving maximum adsorption capacity of 10.04 mg/g and biodiesel yield 67.5%. Moreover, statistical parameters revealed, immobilisation temperature and initial protein concentration influence the catalytic activity considerably and optimised immobilisation helps in attaining highly active and stable biocatalyst. Furthermore, the chosen model was effective in predicting the optimised conditions with high precision for maximising the responses. Thus, the developed biocatalyst through lipase immobilisation on indigenously prepared microporous carbon support is effective in transesterification of MFO at 3FI model derived optimised conditions.