Purpose: An assessment of retinal function topographically in the affected eyes with central serous chorioretinopathy (CSC).Participants and Method: We recorded multifocal electroretimogram (mERG) in 5 patients with unilateral CSC, and analyzed the topographical properties in the central visual field (rings #1 + 2).Results: mERG amplitudes in the CSC eyes were significantly reduced compared with the fellow eyes, for P 1-N 1 (58.5 +/- 23.5%, p < 0.05) and for P 1-N 2 (47.5 +/- 15.0%, p < 0.05). mERG latencies in the CSC eyes were significantly increased compared with those in the fellow eyes, for N 1 (by 9.0 +/- 8.1%, p < 0.05) and for P 1 (by 8.4 +/- 7.0%, p < 0.05). mERG in the CSC eyes gradually recovered in the follow-up period. However, the responses did not recover to normal value during follow-up, even when the subretinal fluid disappeared ophthalmoscopically.Conclusions: These results show that a topographical analysis of the mERG is useful for clinical observation of CSC.