Background: Catheter associated urinary tract infections (CAUTIs) are the most common healthcare associated infections (HAIs). It leads to substantial morbidity in hospitalized patients. Aim: The current study aimed to evaluate the effect of applying nursing guidelines (NG) on reducing CAUTI among critically ill patients (CIPs). Design: A quasi-experimental research design was utilized. Setting: This study was conducted at the Traumatic Intensive Care Unit (TICU), Minia University Hospital (MUH), at Minia City (MC), Egypt. Subjects: A purposive sample of 60 patients of both sexes was divided into intervention and control groups. The intervention group (IG) received the NG for preventing CAUTIs, while the control group (CG) received routine hospital nursing care. Tools: Two tools were used: First Tool: Patient Health Assessment (PHA, includes two parts, First Part: Demographic Data (DD) Second Part: Medical Data (MD) Second Tool: Catheter Associated Urinary Tract Infection Checklist (CAUTIC). Results: there was a low percentage of infection manifestation among IG compared to CG having the highest percent at the 4^th, 5^th, and 6^th days. Nursing guidelines to prevent CAUTIs had success in reducing the incidence of CAUTIs among IG and improving patient outcomes. There was a correlation between respiratory rate and CAUTI criteria among IG and CG at the 3^rd and 6^th days, with a highly statistically significant difference. Conclusion: Implementation of the nursing guidelines lowers the incidence of CAUTI among the IG compared to the CG. Recommendations: Replication of the recent study on a larger probability sample from dissimilar geographical settings to generalize the finding.