Purpose: To assess local retinal function of macula in patients with central serous chorioretinopathy (CSC). Methods: Multifocal electroretinograms (ERGs) were recorded in 5 patients with unilateral CSC and 20 normal subjects. The waveforms from the central retina within 5° of visual angle were analyzed. The first negative trough was designated as N1, the first positive peak as P1, and the second trough as N2. Results: The multifocal ERG amplitudes were significantly reduced at the first attack of CSC in all patients compared with the values in the normal controls, for P1–N1 ( P < .01) and for P1–N2 ( P < .01). Multifocal ERG latencies of the patients significantly increased compared with normal controls, for P1 ( P < .01) and N2 ( P < .01). After the resolution of retinal detachment, although the multifocal ERG amplitudes increased markedly, they did not improve to the normal level during the follow-up period (4–23 months). Conclusions: Persistent functional impairment of the retina was found by multifocal ERGs in patients with CSC after the resolution of subretinal fluid. A topographical analysis of the multifocal ERG is useful in the clinical observation of CSC.