PURPOSE To compare the effect of suction on macular and retinal nerve fiber layer thickness during femtosecond lenticule extraction and femtosecond laser-assisted laser in situ keratomileusis (LASIK) with the Visumax FS system. SETTING Ophthalmic Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology & Visual Sciences Key Lab, Beijing, China. DESIGN Prospective comparative case series. METHODS Fourier-domain optical coherence tomography was used to measure macular and retinal nerve fiber layer thickness preoperatively and through 6 months postoperatively. RESULTS The study evaluated 196 eyes. In the femtosecond lenticule extraction group, the mean foveal, parafoveal, and perifoveal retinal thicknesses 1 day and 1 week postoperatively were diminished, although the changes were not statistically significant. The retinal thickness did not change significantly 1, 3, or 6 months postoperatively (P>.05). In the LASIK group, the mean foveal, parafoveal, and perifoveal retinal thicknesses did not change significantly at any postoperative timepoint (P>.05). The differences in all 3 retinal thicknesses between the 2 groups were not significant 1, 3, or 6 months postoperatively (P>.05). The ganglion cell complex and retinal nerve fiber layer thickness did not change significantly from preoperatively to any postoperative timepoint in either group (P>.05). CONCLUSION Suction had no significant clinical effects on the macular thickness and retinal nerve fiber layer during femtosecond lenticule extraction or femtosecond laser-assisted LASIK.