Back ground: awareness of pregnant woman about iodine deficiency is a very important issue since it cause a wide spectrum disorders include still birth, increase number of spontaneous abortion, congenital abnormalities, and irreversible mental retardation to the fetus. Aim: To assess pregnant woman's awareness regarding iodine deficiency. Subject and method: research design: a descriptive study design was used. Subject: a purposive sample of 350 pregnant women was recruited in the study. Setting: the study was conducted at outpatient antenatal clinic at Central Touch Hospital, Qalyubia. Tool of data collection: include: 1-pregnant woman's general characteristics tool. 2- pregnant woman's past and current medical and obstetric history tool. 3- assessment pregnant woman's knowledge regarding iodine deficiency tool. Results: it revealed that more than three quarters of the study sample had unsatisfactory knowledge regarding iodine deficiency and about one quarter of them had satisfactory knowledge and there were a statistical significant relation between studied sample demographic characteristics and their total level of knowledge regarding iodine deficiency. Conclusion: The current study reveals that, more than three quarters of the studied sample had unsatisfactory knowledge regarding iodine deficiency disorders and about one quarter of them had satisfactory knowledge. Recommendations: Strategies should include nutritional educational programs for pregnant women to improve their knowledge regarding iodine deficiency.