Background: Urinary tract infections are the most typical bacterial infection that can occur during pregnancy, and they are the cause of a number of issues that can harm the mother as well as the fetus. Good management based on accurate information and more satisfying self-care practices is key to prevent these issues. Aim of the study: To evaluate the effect of instructional guidelines on knowledge and self-care practices of pregnant women with urinary tract infections. Subjects and method: Research design: Quazi experimental design (pre/post-test). Setting: The study was carried out at antenatal care unit in outpatient clinic, at Zagazig University Hospital. Subjects: A purposive sampling of 120 pregnant women with urinary tract infections were enrolled and equally divided into intervention and control groups. Tools of data collection: Three tools were used. Tool I: A structured interviewing schedule which composed of 3 Sections, Tool II: Severity of urinary tract infections symptoms assessment scale and Tool III: Self-assessment interviewing schedule: To assess pregnant women's self-care health practices for urinary tract infections. Results: There was a highly statistically significant improvement in total score of all areas of knowledge and total score of self- care practices post intervention in the intervention group than those in control one. Also, there was a highly statistically significant difference in the improvement of urinary tract infection symptoms as reported by pregnant women in intervention group as compared to control group after applying the nursing guidelines. Conclusion: The instructional guidelines have been an effective intervention to improve the knowledge of pregnant women and give suitable self-care practices of urinary tract infections that lessen the severity of symptoms. Recommendations: All pregnant women should take part in a continuing health education program to better understand urinary tract infections and prevent them from occurring again throughout pregnancy. Keywords: Instructional Guidelines, Knowledge, Self-care practices, pregnant women, urinary tract infections.