An increasing number of studies examined the potential effects of PM1 (submicronic particulate matter with an aerodynamic diameter 1 μm) on the risk of respiratory diseases; however, the results have been inconclusive. This study aimed to determine the overall association between PM1 with total and cause-specific respiratory diseases. A systematic review and meta-analysis was conducted with 68 related articles retrieved, and six articles met the full inclusion criteria for the final analysis. For a 10 μg/ m3 increase in PM1, the pooled odds ratio (OR) was 1.05 (95% CI 0.98 1.12) for total respiratory diseases, 1.25 (95% CI 1.00 1.56) for asthma, and 1.07 (95% CI 1.04 1.10) for pneumonia with the I2 value of 87%, 70%, and 0%, respectively. Subgroup analyses showed that long-term exposure to PM1 was associated with increased risk of asthma (OR 1.47, 95% CI 1.33 1.63) with an I2 value of 0%, while short-term exposure to PM1 was not associated with asthma (OR 1.07, 95% CI 0.89 1.27) with the I2 value of 0%. Egger s test showed that publication bias existed (P = 0.041); however, the funnel plot was symmetrical with the inclusion of the moderator. In conclusion, elevated levels of PM1 may increase morbidity in total and cause-specific respiratory diseases in the population.