<p>At all levels of healthcare, accurate and timely immunization data are essential for informing decisions and enhancing program effectiveness. The capacity to achieve program goals and achieve meaningful vaccination coverage may be hampered by poor data quality. However, there is not enough concrete information to support the measures that should be made in this situation. This study's primary goal was to evaluate the level of routine immunization data quality and associated factors among health facilities in the Angwaa Zone, Gambella area, southwest Ethiopia.</p>