A growing number of studies have associated short-term exposure to ambient particulate matter air pollution (PM) and risk of specific cardiovascular events, just as myocardial infarction (MI). However, the results of the recent studies were inconsistent; therefore, a systematic review and meta-analysis was performed. To synthetically quantify the association between short-term exposure to PM and risk of MI, a meta-analysis was conducted to combine the estimates of effect for a relationship between short-term exposure to PM10, P M2.5(particulate matter≤10 μm, 2.5 μm i n d i a m e t e r ) and risk of MI. Electronic database searches for all relevant published studies were updated in January 2015. And, a random-effects model was performed to estimate pooled relative risk (RR) and 95 % confidence intervals (95 % CI). Thirty-one published observational epidemiological studies were identified. Risk of MI was significantly associated with per 10μg/m3increment in PM10(OR=1.005; 95 % CI 1.001– 1.008) and PM2.5(OR=1.022; 95 % CI 1.015–1.030). The risk of PM2.5exposure was relatively greater than PM10. I n the subgroup analysis by study design, location, quality score, and lag exposure, the results were basically consistent with the former overall results in PM2.5but slightly changed in PM10. Short-term exposure to particulate matter (PM2.5,P M10) was a risk factor for MI, and the results further confirmed the discovery in the previous meta-analysis.