In this study, microwave-heated biodiesel production from catalyzed transesterification of beef tallow was investigated for a range of reaction times between 10-30 min, temperatures between 40-60 degrees C, amounts of alkali catalyst between 0.25-0.75% w/w, and tallow to methanol molar ratio between 1:3 to 1:9. Results showed that fast conversion of beef tallow into biodiesel can be obtained with microwave heating. High biodiesel yields of 98% with an ester content over 96.5% can be achieved within 10 min at a molar ratio of 1:6, a catalyst concentration of 0.75%, and reaction temperature of 60 degrees C.