Background: Early discharge after successful primary angioplasty is common, but the evidence supporting the practice is still lacking. We therefore performed a meta-analysis assessing the safety of early discharge after primary angioplasty in low-risk patients with ST-segment elevation myocardial infarction (STEMI). Methods: Randomised controlled trials were identified and extracted from PubMed, Embase, Cochrane Library databases and reference lists of relevant papers. Heterogeneity was analysed using the I 2 test. If there was a lack of heterogeneity, fixed effects models would be used for the meta-analysis, otherwise random effects models were used. Statistical analyses were performed using Review Manager 5.3. Results: Five randomised controlled trials involving 1575 STEMI patients met the criteria. Meta-analysis showed that the early discharge strategy group had a significantly shortened length of hospital stay compared to the conventional discharge strategy group (standardised mean difference -1.46, 95% confidence interval (CI) -2.04 to -0.88; P < 0.0001), and there was no difference in mortality and readmission rates between the two groups (risk ratio 0.78, 95% CI 0.50 to 1.22; P = 0.41). Conclusions: The findings of this meta-analysis suggested that the early discharge strategy after successful primary angioplasty is safe among selected low-risk STEMI patients. A shorter hospital stay could benefit both the patients and the healthcare systems.