ABSTRACT: Background: Confirmation of malaria and appropriate treatment are keys to malaria control. Objective: To determine the practice of malaria diagnosis and treatment in a Nigerian tertiary hospital. Materials and Methods: Retrospective review of patients’ records at the Children’s Clinic in UNTH. Results: Out of 6,684 children seen within the one year reviewed period, children diagnosed with malaria were 35.8 percent. Males were 60 percent and females were 40 percent. Children under five years were 72.6 percent of the total. Folders successfully traced were 1012; in 92 percent investigations for malaria were requested while 32 percent had differential diagnosis. Out of the 931 malaria investigations requested, 30percent did the tests and positive results were 94.9 percent. Presumptive treatment was 98 percent. Majority (83.3%) received ACTs. Conclusion: The practice of presumptive treatment was high and few cases had a differential diagnosis. Training of health workers on the need to confirm malaria cases is required.