Background: Immediate postpartum anemia is a condition where hemoglobin concentrations are lower than normal, which complicates maternal lives, including death. But so far, studies across Ethiopia have been inconsistent and lacking in the study area. Therefore, this study was aimed at assessing the magnitude and predictors of immediate postpartum anemia among singleton postpartum women which could help in interventions. Methods: A cross-sectional study was conducted in May 2022 in the public hospitals in Dire Dawa, Ethiopia. Participants were selected using a systematic random sampling technique. Data were collected using a structured questionnaire and medical card review, entered into EPI DATA (version 3.1) and analyzed using statistical package for the social sciences (SPSS) (version 22). A p value of 0.05 or less at multivariate with 95% confidence intervals was considered statistically significant. Results: Of 476 participants, 26.9% had immediate postpartum anemia and significantly associated with lack of formal education (AOR=3.01, 95% CI: 1.12–8.08), unemployment (AOR=2.72, 95% CI: 1.02–7.21), number of ANC visits (AOR=2.40, 95% CI: 1.32–4.30), instrumental delivery (AOR=3.70, 95% CI: 1.952–6.86), pre-delivery anemia (AOR=2.96, 95% CI: 1.48–5.91), gastro-intestinal parasites (AOR=3.23, 95% CI: 1.37–7.59), low dietary diversity (AOR=3.10, 95% CI: 1.65–5.79), and no iron supplementation during pregnancy (AOR=2.69, 95% CI:1.10–6.58). Conclusions: Almost one in four singleton postpartum women had immediate postpartum anemia. Findings indicate a public health problem and interventions need on risk factors.