Introduction: Suicide is the leading cause of unnatural death among people with a diagnosis of schizophrenia. Alcohol use is a prevalent comorbid feature of schizophrenia and a modifiable risk factor for suicide. We conducted a prospectively registered (PROSPERO, CRD42022358214) systematic review and meta-analysis to quantify the relationship between alcohol use and suicide-related outcomes in schizophrenia. Methods: We searched Medline, Embase, and PsycINFO for cross-sectional, case–control and longitudinal studies using exhaustive terms from database inception to December 2022 inclusive. Computation of odds ratios (ORs) and hazard ratios (HRs) were performed using a random-effects model with DerSimonian–Laird estimation. We also evaluated publication bias, study quality, and performed subgroup analysis and meta-regression. Results: Fifty studies, comprising 65 samples, met eligibility criteria. Overall, alcohol use was associated with suicide (OR 1.38, 95% CI 1.21–1.58; HR = 1.32, 95% CI 1.00–1.74), attempted suicide (OR 1.69, 95% CI 1.45–1.98), and suicidal ideation (OR 1.69, 95% CI 1.22–2.34). While there was no evidence of publication bias, between-sample heterogeneity was moderate in analyses of attempted suicide (I2 = 39.6%, p = 0.01) and suicidal ideation (I2 = 56.0%, p = 0.01). Summary effects were significant in all subgroups except for longitudinal studies of attempted suicide (OR 1.60, 95% CI 0.86–3.00) and studies of suicidal ideation using gender combined samples (OR 1.63, 95% CI 0.99–2.67). Discussion: Alcohol use is significantly associated with suicidal thoughts, attempts and deaths in schizophrenia. However, the psychological mechanisms that underlie pathways to suicidal experiences in people with schizophrenia that involve the use of alcohol are poorly understood. An in-depth examination of both reasons for alcohol use and the effects that alcohol use have on suicide-related thoughts, cognitions, and emotions is vital, using convergent methods based on diary and qualitative methodologies and analyses.