To evaluate the evidence about the safety and efficacy of tramadol in pain relief during diagnostic outpatient hysteroscopy (OH). Systematic review and meta-analysis of randomized controlled trials. Not applicable. Patients undergoing diagnostic OH received tramadol versus those who were administered placebo. Electronic databases were searched using the following MeSH terms (tramadol OR opioids OR opioid OR narcotic OR narcotics) AND (hysteroscopy OR hysteroscopic). Pain assessed by visual analogue scale (VAS) during OH, immediately and 30 minutes after the procedure. One hundred thirteen studies were identified of which four randomized clinical trials were deemed eligible for this review (tramadol: n = 209; placebo: n = 209). The pooled estimate showed that tramadol significantly reduced VAS during procedure than placebo (weighted mean difference WMD = -1.33; 95% confidence interval CI -1.78 to -0.88, I = 3%, P = .36). In addition, tramadol significantly reduced VAS immediately after the procedure (WMD = -1.05; 95% CI -1.49 to -0.61, I = 0, P = .84) and 30 minutes after (WMD = -0.98; 95% CI -1.30 to -0.65, I = 0, P = .88). This meta-analysis suggests that tramadol is safe, effective, and gives favorable results in reducing pain during diagnostic OH.