AIM: To analyze the efficacy and safety of subthreshold micropulse laser (SML) in the treatment of acute central serous chorioretinopathy (CSC). METHODS: This is a retrospective case analysis study. Totally 58 eyes of 58 patients were enrolled, and they were divided into different groups. And 39 patients were treated with SML (SML group) and 19 patients were only observed (observation group). The follow-up period was 3mo after diagnosis. The best corrected visual acuity (BCVA), central retinal thickness (CRT), superficial retinal vascular density (SRVD), deep retinal vascular density (DRVD), the superficial and deep foveal avascular zone (FAZ) area, retinal light sensitivity (RLS), perfusion area of choroidal capillary layer (CCL), subfoveal choroidal thickness (SFCT) and fundus autofluorescence (FAF) were investigated. RESULTS: The BCVA, CRT, SRVD, DRVD, the superficial and deep FAZ area, RLS, SFCT of SML group were significantly improved at 3mo (all P<0.05). In the observation group, only CRT, DRVD and SFCT were improved (all P<0.05). Other research items in the observation group were not significantly different from baseline (all P>0.05). At the last follow-up, the BCVA and RLS in the SML group were better than those in the observation group, and CRT was lower, SRVD and DRVD, perfusion area of CCL were larger (all P<0.05). On FAF, no change of treatment spots was found after treatment. No structural laser damage was observed on optical coherence tomography (OCT) and optical coherence tomography angiography (OCTA), and no choroidal neovascularization was observed. CONCLUSION: SML treatment of acute CSC can improve BCVA, RLS, and perfusion area of CCL, reduce CRT, increase SRVD and DRVD, and is safe.