Background: Immunization has shown a major preventive aspects of infectious diseases, disability and death. Objectives:  Assessing the Knowledge, attitude and practice (KAP) of Saudi parents in Jeddah City regarding the immunization programs for children, Saudi Arabia (KSA), 2017. Methods: It is a cross sectional survey study that was carried among 600 different Saudi parents form different parts of Jeddah City for 3 months from May to July 2017. The parents completed a questionnaire that contains 4 different parts about the demographics, knowledge, attitude and practice of parents   toward immunization. Results: The included parents have shown a high level of awareness about vaccination regarding the preventive measures and importance of vaccination which resulted in positive attitudes and practice pattern among most of them. The overall KAP was good among most of parents (87.2%). The higher KAP level was significantly associated with female gender, higher educational degree and having higher number of children. Conclusion: Most of Saudi parents had good KAP toward immunization which was associated with female gender and higher educational degrees. However, educational programs are still needed to increase the parents' knowledge and practice especially among illiterate and less educated parents living in rural areas.