OBJECTIVE: To evaluate the marginal microleakage of IPS-Empress 2 all-ceramic crowns using three different cements. METHODS: Twenty-four IPS-Empress 2 all-ceramic crowns were built and luted onto standardly prepared human upper third molars using three different cements. All samples were thermocycled then submerged in 2% fuchsin for 24 hours. The marginal microleakage at tooth-cement and ceramic crown-cement interfaces was observed using light stereomicroscopy. RESULTS: The Panavia F adhesive luting system demonstrated the least microleakage(0.90+/-0.75, 0.46+/-0.37). Dyract compomer cement showed an intermediate level of microleakage (4.71+/-1.68, 5.28+/-1.48). Harvard zinc phosphate cement was associated with severe microleakage in all specimens( 6.99+/-0.04, 6.99+/-0.04). THe differences in microleakage among the three cements was highly significant(P<0.01). CONCLUSION: Panavia F adhesive luting system was the most effective dental cement to prevent microleakage. It can be used for IPS-Empress 2 posterior all-ceramic crowns.