Smoking among women is increasing, especially in women of reproductive age. In a cross-sectional study of 1000 Lebanese mothers, we evaluated their knowledge, attitude and practice regarding cigarette smoking. We found that the amount of tobacco smoked by Lebanese mothers was related to age, educational level, profession and knowledge regarding smoking. A woman was more likely to stop or decrease smoking during pregnancy if she were more knowledgeable about the effects of smoking on the baby, if she smoked less, and if she had a higher degree of education. Knowledge about the effects of smoking on the smoker did not seem to affect this practice