Introduction: Acute kidney injury (AKI) is a persistent disorder that acts as a morbidity and mortality factor in hospitalized older adults. It is a public health problem associated with several factors, some modifiable. Methods: An analytical cross-sectional study was conducted in Cuenca in the HVCM emergency service from March 2018 to March 2020. The sampling was probabilistic, evaluating 200 older adults. The KDIGO (Kidney Disease: Improving Global Outcomes) criteria were used to determine and classify AKI. The data were analyzed with the SPSS v.20.0 program, using the prevalence ratio (PR) to measure association, with a 95% CI and statistical significance P <0.05. Results: The mean age was 80 ± 8.37 years, the female gender predominated, and the majority had a primary education level. The prevalence of AKI was 33%. Four out of ten older adults had AKI stage 3, and more than half had high blood pressure and use nephrotoxic. The associated factors were sepsis (PR 2.27; 95%CI 1.58- 3.27; P =0.0002), dehydration (PR 1.73; 95%CI 1.18-2.54; P =0.006), and diabetes mellitus (PR 1.58; 95% CI 1.07– 2.34 P =0.0181). Conclusion: more than a third of hospitalized older adults presented AKI; KDIGO stage 3 predominated and was associated with sepsis, dehydration, and diabetes mellitus