Mono alkyl glycerides have bean obtained in good yield by enzyme catalyst from soybean oil. The reaction was carried out in an oil rich microemulsion formula. Best results were obtained with sodium bis(2-ethyl hexyl) sulfo succinate(AOT), isooctane as hydrocarbon component and buffer of pH 7. The enzyme used was a 1, 3-specific lipase which leaves the 2-position intact. However, the 2-monoglyceride formed slowly undergoes long chain acyl migration to 1-mono-glyceride. Optimal reaction time at 35℃ reaction temperature was found to be three hour.