Wax esters are long-chain esters that have been widely applied in premium lubricants, parting agents, antifoaming agents and cosmetics. In this study, the biocatalytic preparation of a specific wax ester, cetyl octanoate, is performed in n-hexane using two commercial immobilized lipases, i.e., Lipozyme ？ RMIM ( Rhizomucor miehei) and Novozym ？ 435 ( Candida antarctica). Response surface methodology (RSM) and 5-level-4-factor central composite rotatable design (CCRD) are employed to evaluate the effects of reaction time (1–5 h), reaction temperature (45–65 °C), substrate molar ratio (1–3:1), and enzyme amount (10%–50%) on the yield of cetyl octanoate. Using RSM to optimize the reaction, the maximum yields reached 94% and 98% using Lipozyme ？ RMIM and Novozym ？ 435, respectively. The optimum conditions for synthesis of cetyl octanoate by both lipases are established and compared. Novozym ？ 435 proves to be a more efficient biocatalyst than Lipozyme ？ RMIM.
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