The process of resolution of ibuprofen by enzymatic esterification was explored using racemic ibuprofen as the reaction substrate. The racemic ibuprofen was selectively esterified by CAL-B. The reaction conditions were optimized, such as the type of alcohol, the reaction medium, the molar ratio of substrate, the amount of enzyme, the type and amount of desiccant, temperature and time. Optical pure S-ibuprofen was obtained with a yield of 56%. Chemical racemization of the esterification product was then carried out. Dimethyl sulfoxide was used as the reaction medium, racemic reaction of ibuprofen was catalyzed by lithium diisopropylamide, enzymatic resolution after complete racemization can still achieve the previous effect. The utilization rate of ibuprofen can reach more than 90% after seven cycles.