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Objective Our objective was to synthesize epidemiological findings on occupational exposure to respirable crystalline silica (RCS) and lung cancer, and to evaluate whether the relationship between RCS and lung cancer was modified by sex, histological type, adjustment for smoking, or study quality.Methods We conducted a systematic review and meta-analysis of cohort and case-control studies reporting risk estimates for lung cancer associated with occupational RCS exposure. Literature searches were applied across five databases with no restrictions on year, language, or region. A total of 1,783 studies were identified, of which 71 met the eligibility criteria. Meta-analyses were conducted in STATA using random effects models.Results Workers ever exposed to RCS had an increased risk of lung cancer (summary meta-risk estimate (mRE)=1.17; 95% CI: 1.07–1.28) relative to those not exposed. In higher quality studies, the risk was higher (mRE=1.19; 95% CI: 1.01–1.39). We found that RCS was associated with an increased risk of lung cancer in both men and women, although we lacked power to assess any differences as only 3 studies reported risks for women. Stronger associations were found for squamous cell carcinoma (mRE=1.41; 95% CI: 1.28–1.55), and among smokers (mRE=2.10, 95% CI: 0.86–5.14). Adjustment for smoking attenuated the summary risk estimate but it remained elevated. Exposure-response analyses are ongoing and will be presented.Conclusion These findings further corroborate the evaluations from past authoritative reviews that occupational exposure to RCS increases the risk of lung cancer. There remains an important need to conduct additional epidemiological studies to capture the risk more accurately in certain subgroups, particularly in women, and by histological type.