Purpose: To compare the choroidal thickness before and after pars plana vitrectomy for rhegmatogenous retinal detachment repair.Methods: A retrospective case series of rhegmatogenous retinal detachment patients presenting between January 2015 and September 2020. Subfoveal choroidal thickness (SFCT) and anatomical success were measured in operated eyes and fellow eyes at presentation, as well as 3 months and 6 months after pars plana vitrectomy for rhegmatogenous retinal detachment repair.Results: A total of 93 patients (males 59%) with a mean age of 61.8 ± 15.2 years were included. Eighty-one patients were anatomically successful (Group 1) and 12 redetached (Group 2). The mean SFCT of the operated eye at presentation was 258.3 ± 82.0 mm in comparison with 257.5 ± 83.7 mm in the fellow eye (P = 0.96). Group 2 presented with thicker SFCT than Group 1 at baseline (309.2 ± 56.2 vs. 250.7 ± 82.8 mm; P = 0.01). Both groups demonstrated thinning trend throughout follow-up. At 6-month follow-up, the mean SFCT was 225.6 ± 75.5 mm (P = 0.05). Fellow-eye SFCT was stable throughout follow-up (257 ± 83.7 at baseline vs. 255 ± 80.2 mm at 6 months).Conclusion: Eyes with rhegmatogenous retinal detachment demonstrated thinning in the SFCT after vitrectomy surgery. Eyes with recurrent retinal detachment presented with a thicker choroid at baseline. Thicker SFCT at presentation may play a role in retinal redetachment.