OBJECTIVE: To evaluate the diagnostic and antibiotic treatment strategies for patients suspected of sepsis, in a tertiary hospital in Indonesia. This can identify areas for improvement in care provided, and inform diagnostic and antimicrobial stewardship activities within the hospital. METHODS: Retrospective review of medical records with regards to the diagnosis and management of adult patients with sepsis admitted to a tertiary hospital in Indonesia. We assessed the diagnostic process, and whether or not the antibiotic treatment provided was appropriate for the diagnosis. Appropriateness of antibiotic treatment was classified as being definite appropriate, probable appropriate, inappropriate, or unknown. RESULTS: The study included 535 adult patients, of whom 295 (55%) were diagnosed with a community-acquired sepsis, and 240 (45%) with a hospital-acquired sepsis. A specimen for culture and antimicrobial susceptibility testing was collected from three out of four patients (392/535). All but 10 patients had information on antibiotic treatment at the time of sepsis diagnosis. Of those, nearly 50% (257/525) of the patients received antibiotic treatment with unknown appropriateness because no cultures were taken (n = 141) or all cultures were negative (n = 116). Just 3.4% and 9.1% of the patients received definite or probable appropriate antibiotic treatment, respectively. CONCLUSIONS: There is a clear need in encouraging attending physicians to obtain the much-required blood cultures, or cultures from the suspected source of infection before empirical antibiotic treatment is started. This will improve the use of appropriate antibiotic treatment strategies, and contribute to antimicrobial stewardship.