Vaccination is the administration of a vaccine to stimulate a protective immune response that prevents disease in the vaccinated person if contact with the corresponding infectious agent occurs subsequently. Thus vaccination, if successful, results in immunization. Immunization prevents millions of deaths every year and reducing the risk of disability caused by infectious diseases. The poorest children typically have access to a smaller range of vaccines and are at greater risk from the hazards of unsafe immunization practices. This descriptive cross-sectional communitybased study has been conducted in Eldaein in 2020 to investigate the contributing factors of incomplete childhood primary vaccination. 381 participants were selected by multi-stage sampling techniques and data was collected by questionnaire and analysis by using the SPSS program, and χ2 tests. The study revealed that 13.9%, 14.4%, 36.1% and 13.4% of the participants experience complications from previous vaccination, long-distance, difficult transportations to the health facilities, respectively. The study also revealed that educational level and household monthly income have a statistically significant association with the attitudes towards the effectiveness of vaccine at p>0.05, while age and household size have a statistically insignificant association with the attitudes towards the effectiveness of vaccine at p<0.05. From the result, it is clear that the level of education affects the attitude of the participants towards the effectiveness of immunization. The study recommended that; the East Darfur Ministry of Health should conduct health education programs towards vaccination.