Although alkyl sulfonates are commonly used for alkylating agents, there are very few reports on phase-transfer-catalyzed asymmetric alkylation with alkyl sulfonates. Herein, we report that the asymmetric reaction using glycine Schiff base 1 and optically pure epoxy triflates op-2 proceeded smoothly in the presence of phase-transfer catalyst (S,S)-4a to furnish gamma,delta-epoxy-alpha-amino acids 3 in good yield with high enantioselectivity.