Background: Vitamin D insufficiency was seen in kids with various infections. Aim:  This study aimed to assess the influence of vit D insufficiency on UTI in kids. Patients and methods: This case-control investigation involved ninety kids between one and twelve years in the Outpatient and Inpatient of the Pediatric Department, Suez Canal University Hospital. Results: There was   significant variance among vit D level in the two study groups (p < 0.001). Fever was the most frequent sign in the case group (80%), while dysuria was the most frequent symptoms (60%). The most common organisms identified in the urine culture was E. coli (75.6%). In the urine analysis, the study showed one quarter of the patients had 20-50 pus cells whereas more than 85% of the controls had pus cells below 10 (p < 0.001). Linear regression analysis revealed that there was a decrease by 14.26 units in the vitamin D level of patients suffering from UTI compared to healthy controls. Conclusion: We found that concentration of vit D was lesser in kids with UTI than without, also there was correlation among concentration of Vit D and development of UTI manifestations, and moreover there was a decrease by 14.26 units in the concentration of vit D of cases suffering UTI compared to healthy controls.