Purpose To evaluate spectral domain optical coherence tomography (SD-OCT) findings of 42 eyes with pars planitis and to identify risk factors affecting visual acuity. Methods Medical records and SD-OCT findings were retrospectively reviewed. Results Mean best-corrected visual acuity (BCVA) was 0.248 +/- 0.3 on the logMAR scale at baseline. SD-OCT findings included epiretinal membrane (ERM) in 16 (38.1%) eyes, loss of normal foveal contour appearance in 8 (19.0%), ellipsoid zone (EZ) damage in 5 (11.9%), external limiting membrane (ELM) damage in 3 (7.1%), disruption of retinal pigment epithelium (RPE) in 2 (4.8%), and macular atrophy in 1 (2.4%). There was macular edema in 10 (23.8%) eyes [cystoid macular edema (CME) in 8 (19.0%), diffuse macular edema (DME) in 6 (14.3%), and serous retinal detachment in 2 (4.8%)]. The mean central macular thickness (CMT) was 272.1 +/- 319.5 mu m. Patients were followed up for a mean of 50.6 +/- 36.7 months. Mean BCVA was 0.210 +/- 0.3 at the final evaluation. SD-OCT findings included ERM in 28 (66.7%) eyes, EZ damage in 6 (14.3%), ELM damage in 3 (7.1%), disruption of RPE in 4 (9.5%), loss of normal foveal contour appearance in 12 (28.6%), and macular atrophy in 2 (4.8%). There was CME and/or DME in 6 (14.3%) eyes. The mean CMT was 238 +/- 220.9 mu m and was significantly lower than the baseline (p < 0.001). According to multivariate linear regression analysis, the presence of DME, and loss of normal foveal contour appearance at baseline were the independent factors associated with BCVA at the final examination (B = 0.726, p < 0.001; B = 0.766, p < 0.001, respectively). Conclusions DME and loss of normal foveal contour appearance were more likely to have adverse effects on visual acuity.