Background: Acute kidney injury (AKI) is a syndrome associated with high morbidity, mortality and high hospital costs. Despite its adverse clinical and economic effects, only a few studies have reported reliable estimates on the incidence of AKI in sub-Sahara Africa. We assessed the incidence and associated factors of AKI among medical and surgical patients admitted to a tertiary hospital in Ghana. Methods: A prospective cross-sectional study was conducted among one hundred and forty-five (145) consecutive patients admitted to the medical and the surgical wards at the Cape Coast Teaching Hospital (CCTH), Cape Coast, Ghana from April 2017 to April 2018. Socio-demographic and clinical information were collected using structured questionnaires. AKI was diagnosed and staged with the KDIGO guideline, using admission serum creatinine as baseline kidney function. Results: The mean age of the study participants was 46.6±17.7 years, whilst the male:female ratio was 68:77. The overall incidence of AKI among the participants was 15.9% (95% CI: 10.33 – 22.84%). Stage 1 AKI occurred in 56.5% of the par- ticipants, whilst stages 2 and 3 AKI respectively occurred among 4.1% and 2.8% of respondents. About 20% of the partic- ipants in the medical ward developed AKI (n= 15) whilst 12% of those in surgical ward developed AKI (n= 8). Among the participants admitted to the medical ward, 60.0%, 26.7% and 13.3% had stages 1, 2 and 3 AKI respectively. Whilst 50.0%, 25.0% and 25.0% respectively developed stages 1, 2 and 3 AKI in the surgical ward. Medical patients with AKI had hyper- tension (40%), followed by liver disease (33.3%); 37.5% of surgical inpatients had gastrointestinal (GI) disorders. Conclusion: The incidence of AKI is high among medical and surgical patients in-patients in the CCTH, Ghana, with hy- pertension and liver disease as major comorbidities. Keywords: Acute kidney injury; KDIGO; medical; surgical; hypertension; liver disease.