Background: Renal failure has elevated to a global public health issue as the total number of End Stage Renal Failure (ESRF)patients that need renal replacement treatment has been sharply increasing. Peritoneal Dialysis (PD) is a method used for replacement of renal function that it is utilized at the end stage of renal disease beside with the hemodialysis and renal transplantation. Objective: Determine the effect of educational program on nurses' knowledge and care practices for patients undergoing PD. Setting: This study was conducted at the PD units of AL-Karama Hospital, AL-Yarmook Hospital, AL-Kadhmiyia Hospital, Baghdad Teaching Hospital and AL-Kindy Teaching Hospital in Baghdad City, Iraq. Subjects: 64 nurses (male / female) to participate in the present study who providing direct nursing care for patients undergoing PD at the above-mentioned settings. Tools: The researcher developed two tools which used to collect the necessary data; a nurses' knowledge related to patients undergoing PD and a nurses' care practices for patients undergoing PD observational checklist. Results: The study revealed that there was a significant improvement within the studied nurses had fair and good level of knowledge and practice immediately and after one month from the implementation of the program. Also, there were significant differences between knowledge and nurses' care practices in the initial assessment, immediately, and after one month from implementation of the program. Conclusion: The educational program has a positive effect on the nurses who attend the educational program and achieve a higher mean score of knowledge and care practices for patients undergoing PD than before the educational program. Recommendations: Establishment of a central in-service educational department in a hospital to renew nurses' knowledge and practice on a regular basis. Continuous nurses knowledge and practices evaluation on PD procedure competency should be taken into consideration.