Emergency contraception is an effective method for preventing unplanned pregnancy. Aim of this study: Evaluate the effect of instructional guideline on women's knowledge and utilization regarding emergency contraceptive methods. Research Design: A quasi experimental. Setting: The study was conducted at family planning clinic at governmental health unit in Damanhur, Beheira governorate, Egypt, (Alhilal Service Medical Center). Sample: A purposive sample consists of 169 women. Tools: One tool was used (Structured interviewing Arabic questionnaire for assessing women’s knowledge and utilization regarding using of the emergency contraception). Results: The current study showed that 7.1% of the studied women had satisfactory level of total knowledge towards emergency contraception pre implementation of instructional guideline which changed to 71.0% post implementation of instructional guideline, and showed that 91,7% of the studied women used emergency contraceptive methods post implementation of instructional guideline which changed to 87,6% at follow up phase. Moreover, there was no statistically significant difference in utilization of emergency contraception among the studied women post implementation of instructional guideline compared to follow up phase at (P > 0.05). Additionally, there was a highly statistically significant positive correlation between women’s knowledge towards emergency contraception and their utilization of emergency contraception at post implementation of instructional guideline at p< 0.001. Conclusion: The present study concluded that the instructional guideline succeeded in improving the studied women's knowledge and utilization regarding emergency contraception.Based on this finding,the researcher recommended;Planning and implementing ongoing structured educational classes and programs regarding the use of emergency contraception for all childbearing women at family planning clinics,distribute posters at hospitals and family planning clinics about emergency contraception methods and mass media should be utilized to disseminate correct and relevant information about emergency contraception among childbearing women.