Therapeutic alliance determines medical treatment adherence, the success of psychotherapy, and the effectiveness of care. This systematic review aims at better understanding its determinants. The electronic databases Pubmed, Cochrane Library, and Web of Science were searched, using combinations of terms relating to psychosis and therapeutic alliance. Studies were selected and data were extracted using a PRISMA statement. Forty-one studies were selected, including 20 cross-sectional studies, 10 cohort studies, five randomized controlled trials, four literature reviews, and two retrospective studies. The quality of therapeutic alliance correlates with clinical symptoms, insight, social and family support, the therapist's qualities, the availability of shared therapeutic decision making, and the types of hospitalization. Although current evidence needs to be completed with further studies, it is already clear that group and family psychoeducation, cognitive remediation, community-based psychiatric services, and shared therapeutic decision making are essential approaches in the management of patients with psychosis.