Data of 7695 deliveries during 1985-1992 in four general hospitals neighboring a petrochemical works in Guangzhou were collected. Relationship between air pollution surrounding the plant and adverse pregnancy outcomes (APO) in women living there, including congenital malformation, stillbirth, low birth weight and preterm birth, was analyzed with air monitoring data and exposure assessment indices. Results showed there was difference in incidence rates of APO between lying-in women living in the places with various distance from the plant, and the incidence lowered with the distance prolonging, with a P-value of less than 0.05. Unconditional logistic model was used to control confounding and to estimate relative risks in a study of 325 cases of APO and 390 randomly sampled normal controls. Results indicated the distance between the places where the women living and the plant related to incidence of APO. It suggested air pollution caused by the petrochemical works may be a risk factor for APO in neighbored women.