Background: Bronchitis is acute or choric inflammation of the large airway passages and lungs, which increased mortality rate among infant. The study aimed to evaluate the effect of instructional guidelines on nurses' knowledge and practices regarding care for infants with bronchitis. Design: A quasi-experimental design was applied; this study was conducted at inpatient pediatric department at Benha university hospital affiliated to Benha Governorate. Sample: A purposive sample of 43 nurses and 36 infants hospitalized with bronchitis. Tools: Structured interview questionnaire and follow up observational checklist. Results: this study reflects, a highly statistically differences for mean scores pre/post-test for nurses' knowledge and practices regarding care for infants with bronchitis. Conclusion: nurses' knowledge and practices regarding care for infants with bronchitis were improved post implementing the instruction guidelines than before. Recommendation: Instructions guidelines regarding care of infants with bronchitis should be periodically in pediatric inpatient departments in hospitals.