Problem-solving therapy (PST) is a potential psychological intervention aimed at preventing and treating psychological issues in stroke patients, although its efficacy is not clearly established. This systematic review assessed the effectiveness of PST in improving mental health, functioning, quality of life, and mortality in this population. Six databases were searched for literature indexed through March 2024, including the Cochrane Library, PubMed, Scopus, CINAHL, NeuroBITE, and OTseeker. This review (CRD42023483757) followed the PRISMA guidelines and the Cochrane Library Handbook, utilizing the RoB 2 tool and GRADE system to assess the quality of the evidence. It included eight randomized controlled trials (RCTs) involving 1249 patients with stroke. Among them, five RCTs showed that PST might improve depression. Additionally, individual RCTs demonstrated the efficacy of PST in addressing patient anxiety, apathy, and coping. With respect to mental health, PST might affect patient quality of life and mortality. However, the results of four RCTs demonstrated no effect of PST on patient functioning. The quality of evidence for the outcomes ranged from very low to high. PST may improve mental health, quality of life, and mortality in patients with stroke.