Introduction. Integrated use of postpartum intrauterine contraceptive devices with delivery service during the immediate postpartum period is ideal for both women and health-care providers. However, utilization of intrauterine contraceptive devices during the postpartum period was rare and in Ethiopia, with information regarding uptake of postpartum intrauterine contraceptive devices limited. Objective. Identify determinants of postpartum intrauterine contraceptive devices uptake among women delivering in public hospitals of South Gondar zone, Northwest Ethiopia, 2019. Methods. An unmatched case-control study was conducted in public hospitals of South Gondar, Ethiopia, from August 1, 2019, to November 10, 2019. A total of 140 cases and 280 controls have actively participated in the study. Five hospitals were selected by simple random sampling. Cases were selected consecutively, whereas two controls for each case were recruited by the lottery method. Pretested questionnaires were used to collect data and it was entered into Epidata version 4.4.2. Logistic regression analysis was used to identify variables associated with the use of outcome and adjusted odds ratio with a 95% confidence interval was used to determine the association between independent and outcome variables. Results. Completing secondary education (AOR = 4.5, 95%CI 2.3–8.85), having a total number of children of 3–4 (AOR = 3.6, 95%CI 1.25–10.2), having  ≥ 5 (AOR = 4.7, 95%CI 1.5–15.3), attending 3 antenatal care (AOR = 2.8, 95%CI 1.44–5.6), ever hearing about postpartum IUCD (AOR = 6.6, 95%CI 2.7–16.1), and having counseling from health-care provider about a postpartum intrauterine contraceptive device (AOR = 6.2, 95%CI 2.99–12.8) were significantly associated with uptake of the postpartum intrauterine contraceptive. Conclusion and Recommendation. Completing secondary education, having 3–4 and ≥5 children, attending three antenatal care, ever hearing about postpartum IUCD, and having counseling from health-care providers about the postpartum intrauterine contraceptive device among women were significantly associated with uptake of an intrauterine contraceptive device after birth. Therefore, it is better to advise women to strictly follow their antenatal care, access to information, and provide counseling.