We investigated the prevalence of smoking and factors associated with smoking in infertile Korean women. Smoking status, education, occupation, personal habits, past medical history, current illness, stress level, and menstrual characteristics were collected from self-report questionnaires. The Beck Depression Inventory (BDI) was used to assess the degree of depression. Data on the causes of infertility and levels of six reproductive hormones were collected from medical records. Among 785 women less than 42 years of age, the prevalence of current, secondhand, past, and never smokers were 12.7%, 45.7%, 0.9%, and 40.6%, respectively. Primary infertility was more frequent in secondhand smokers. Causes of infertility were similar among current, secondhand, and never smokers. Current smokers were less educated (P < 0.001) and more likely to consume alcohol than secondhand or never smokers (P < 0.001). Secondhand smokers slept less than current smokers (P = 0.041). Among several major diseases, only the prevalence of diabetes mellitus (4.0%) was significantly higher in current smokers than in secondhand smokers (0.0%, P = 0.002) or never smokers (0.6%, P = 0.031). The self-reported prevalence of depression, and the degree of depression were similar among women with different smoking statuses. There were no differences in menstrual characteristics or serum levels of six reproductive hormones between current, secondhand, and never smokers, even after excluding women with polycystic ovary syndrome. In conclusion, education/employment status, alcohol drinking, and the prevalence of primary infertility and diabetes mellitus were significantly different according to smoking status among infertile women.