Background: Acute kidney injury (AKI) is a common and serious complication of acute febrile illness (AFI), particularly in tropical and resource-limited settings. Infectious diseases such as dengue, malaria, and scrub typhus frequently contribute to the development of AKI and are associated with increased morbidity and mortality. Objectives: To evaluate the clinical profile, etiological spectrum, and outcomes of AKI in patients presenting with acute febrile illness. Methods: This hospital-based cross-sectional analytical study was conducted over a period of 12 months at a tertiary care center in Udaipur, Rajasthan. A total of 100 adult patients (≥18 years) presenting with acute febrile illness of less than 7 days duration were included and evaluated for the development of AKI. Detailed clinical history, physical examination, and laboratory investigations including complete blood count, renal and liver function tests, and serological tests for tropical infections were performed. AKI was diagnosed based on standard clinical and laboratory criteria and classified according to the RIFLE criteria. Patients were followed during hospitalization to assess outcomes including recovery, need for hemodialysis, and mortality. Statistical analysis was performed using SPSS version 25.0, with p < 0.05 considered statistically significant. Results: Among the study population, AKI was observed in a substantial proportion of patients with AFI. Dengue was the most common etiological factor, followed by malaria and scrub typhus. Platelet counts showed a significant increasing trend during hospitalization, while serum creatinine levels initially increased and subsequently decreased, indicating recovery in most patients. Patients with adverse outcomes had significantly higher total leukocyte counts, liver enzyme levels, blood urea, and serum creatinine levels, along with lower platelet counts. A subset of patients required hemodialysis, and mortality was observed predominantly among patients with dengue infection. Conclusion: AKI is a frequent and clinically important complication of acute febrile illness, with outcomes closely related to disease severity and laboratory parameters. Early diagnosis, regular monitoring of renal function, and timely intervention are essential to improve patient outcomes and reduce mortality.