Introduction: Immunization is crucial for preventing infectious diseases in children under five, yet vaccination rates in Iraq are inconsistent due to socio-economic and cultural factors. This study investigates parental knowledge, attitudes, compliance, and barriers to immunization among parents of young children attending Al-Yarmouk Teaching Hospital in Baghdad.

Methods: A cross-sectional design was employed, targeting 300 parents of children aged 0-5. Participants were recruited through convenience sampling in the outpatient department. A structured questionnaire assessed knowledge, attitudes, compliance rates, and barriers to vaccination. Data analysis was conducted using SPSS software, employing descriptive statistics and chi-square tests to examine associations between variables.

Results: Among participants, 72% were mothers, predominantly aged 21-30 (62%). The sample revealed low levels of immunization knowledge: only 19% had good knowledge, while 63% adhered to vaccination schedules. Barriers to compliance included lack of awareness (35%) and family issues (32%). Despite a positive attitude towards vaccination, with 81% agreeing on its necessity, misconceptions—such as beliefs about vaccination for only the first child—persisted. Notably, informants without siblings exhibited higher knowledge rates. The findings highlight significant disparities in knowledge and compliance, influenced by demographic factors such as education, age, and residence. While the majority recognized vaccination's importance, misconceptions and logistical barriers hindered adherence. This underscores the need for targeted educational interventions tailored to specific demographics to enhance vaccination rates.