Objective To analyze the effects of post-stroke depression on sleep quality and cognitive dysfunction, and to provide evidence for the intervention of post-stroke depression. Methods A retrospective analysis was performed on 712 patients with stroke in Shiyan region from October 2018 to October 2020. According to the occurrence of post-stroke depression, they were divided into experimental group (post-stroke depression, n=294) and control group (non-post-stroke depression, n=418). The experimental group was divided into mild group (n=89), moderate group (n=128) and severe group (n=77) according to the HAMD score. PSQI score and MOCA score were compared between the two groups. The Pearson correlation analysis of HAMD score with sleep quality and cognitive dysfunction was analyzed. Results THE PSQI score of the experimental group was significantly higher (t =40.961, P<0.05). The MOCA score of the experimental group was significantly lower (t =27.525, P<0.05). PSQI score in mild group was significantly lower than that in moderate and severe groups (t1 =19.988, t2 =22.634, P<0.05). The PSQI score of moderate group was significantly lower (t3 =7.157, P<0.05). MOCA evaluation in mild group was significantly higher than that in moderate and severe groups (t1 =8.180, t2 =14.568, P<0.05). The MOCA rating of moderate group was significantly higher than that of severe group (t3 =7.947, P<0.05). Pearson correlation analysis showed that post-stroke depression was significantly positively correlated with PSQI score (r=0.713 , P<0.05). Poststroke depression was negatively correlated with MOCA score (r = -0.691, P<0.05). Conclusion The patients with poststroke depression are often accompanied by sleep disorder and cognitive dysfunction. The higher the HAMD score, the more serious the sleep disorder and cognitive dysfunction.