Background: Glaucoma is a leading cause of irreversible visual impairment worldwide. Ophthalmic nurses play a critical role in managing glaucoma surgery patients. Aim of study: This study aimed to evaluate the effect of intervention guidelines on nurses' performance regarding glaucoma surgery at Zagazig University Hospitals. Design: A quasi experimental design was utilized in this study. Setting: Data was collected from department of ophthalmology and ophthalmology outpatient clinic at Zagazig University Hospitals. Subjects: The study was conducted on Convenience sample of all available nurses working in ophthalmology department (40 nurses)Tools of data collection: Two tools were used for collection of data, first, structured interview questionnaire for nurses, Second tool was an observational check list to assess nurses’ practice regarding glaucoma surgery. Results: 72% of nurses aged below 45 years, 95% of them were married, 77% of them had diploma in nursing, 57% of them had more than ten years of experience in ophthalmology department, 95.5% of them didn’t have training course regarding glaucoma surgery. There were statistically significant improvements in mean differences scores of studied nurses' knowledge and practice regarding glaucoma post intervention compared to pre intervention. Conclusion: It can be concluded that the intervention guidelines significantly improved nurses' knowledge and practice regarding glaucoma surgery. Recommendations: It is recommended that periodic evaluation and validation of the training given and training programs should be included both theoretical and practical.