This study aimed to assess the knowledge and attitudes of nurses toward drugs affecting breastfeeding in governmental primary health care (PHC) clinics in the Gaza Strip. A descriptive analytical approach was used to achieve the research objectives. A questionnaire was administered to female nurses working in all 24 PHC clinics under the administration of the Ministry of Health (MOH) in the Gaza Strip. The study sample was selected randomly and consisted of 150 nurses currently employed at governmental PHC clinics in the Gaza Strip. The researcher employed a quantitative, descriptive, and analytical cross-sectional design, with data collection occurring between April and June 2018. Data analysis included frequencies, means, percentages, T-tests, and One-Way ANOVA.The results indicated that half of the participating nurses were aged between 31 and 40 years, and less than half held a bachelor's degree. More than half of the nurses had between 11 and 20 years of experience. The findings also revealed that more than one-third of the nurses were knowledgeable about drugs that affect breastfeeding, and three-quarters of the nurses had positive attitudes toward the use of such drugs.