Objective　To evaluate the effect of modified suction ring in laser in situ keratomileusis(LASIK) for special eyeballs.Methods　Those eyeballs that couldn't be sucked successfully with regular suction ring were performed with modified suction ring, and the characteristic of those eyes was analyzed.Results　Fifteen eyes of 9 cases were included in this study and were sucked successfully with modified suction ring with intact corneal flap.Eight eyes of 5 cases had small corneal power especially in the peripheral section. The corneal power in the peripheral section of 7 eyes was less than 41D. Corneal diameter of 1 eye was 9.5mm and 6 eyes of 3 cases had small palpebral fissure.Conclusions　The modified suction ring is safe and effective for those eyes with flat cornea, small corneal diameter and small palpebral fissure.