We conducted a systematic review and meta-analysis of community empowerment interventions for HIV prevention among sex workers in low- and middle-income countries from 1990-2010. Two coders abstracted data using standardized forms. Of 6,664 citations screened, ten studies met inclusion criteria. For HIV infection, two observational studies showed a significantly protective combined effect [odds ratio (OR): 0.84, 95% confidence interval (CI): 0.709-0.988]. For STI infection, one longitudinal study showed reduced gonorrhoea/chlamydia (OR: 0.51, 95% CI: 0.26-0.99). Observational studies showed reduced gonorrhoea (OR: 0.65, 95% CI: 0.47-0.90), but non-significant effects on chlamydia and syphilis. For condom use, one randomized controlled trial showed improvements with clients (beta: 0.3447, p = 0.002). One longitudinal study showed improvements with regular clients (OR: 1.9, 95% CI: 1.1-3.3), but no change with new clients. Observational studies showed improvements with new clients (OR: 3.04, 95% CI: 1.29-7.17), regular clients (OR: 2.20, 95% CI: 1.41-3.42), and all clients (OR: 5.87, 95% CI: 2.88-11.94), but not regular non-paying partners. Overall, community empowerment-based HIV prevention was associated with significant improvements across HIV outcomes and settings.