Achieving and maintaining high-level immunization coverage is the priority of the health-care delivery system. However, any delay in receiving the vaccine leaves youngsters inadequately protected. Timely vaccination has scarcely been reported and given little attention in developing nations like Ethiopia, which hinders effective interventions. Therefore, this study aimed to assess age-appropriate vaccination practice and associated factors among mothers of children aged less than one year in the pastoral community. A community-based cross-sectional study has conducted among 340 mothers/caregivers of children aged less than one year in Samara-logia city administration. A systematic random sampling technique was employed to identify and enroll mothers-child paired. The logistic regression analysis had done to identify the factors associated with age-appropriate vaccination practice. The statistical association had measured, and a -value < 0.05 was considered statistically significant. In this study, a total of 331 mothers/caregivers-child pairs participated with a response rate of 97.3%. The age-appropriate vaccination practice was 43.7% (95% CI, 38%, 49.5%). Mothers who had higher educational level (Adjusted odds ratio (AOR)) = AOR = 2.89, 95% CI (1.14, 7.3), antenatal care follow-up (AOR = 2.1, 95% CI (1.04, 4.1)), and had good knowledge on vaccination (AOR = 3.1, 95% CI (1.4, 6.78)) were associated with increased odds of age-appropriate vaccination practice.