Background <p>Colostomy is an important emergency procedure to save children’s lives. It is necessary to use a suitable educational program to improve the knowledge and caring performance of parents. Therefore, this study was conducted with the aim of determining the effectiveness of the educational program on the knowledge and caring performance of parents of children with colostomy.</p> Methods <p>This clinical trial study was conducted on 78 parents of children with colostomy. The patients were randomly divided into 39 test groups and 39 control groups using the 4 block method. The data were collected with demographic information questionnaire and parents’ knowledge and care performance questionnaire. Collected data were analyzed using SPSS₂₅, employing descriptive (including frequency, percentage, mean, and standard deviation) and inferential (including paired t-test, independent t-test, chi-square, and analysis of covariance) statistics.</p> Results <p>There is no difference between the control and test groups with demographic characteristics. There was a significant difference between the average score of parental care knowledge after the intervention in the control and test groups (<i>P</i> &lt; 0.001). There was a significant difference between the average score of parental care performance after the intervention in the control and test groups (<i>P</i> &lt; 0.001).</p> Conclusions <p>The educational program can be used as an effective way to increase the knowledge and care performance of parents of children with colostomy and to control complications caused by colostomy.</p> Trial registration <p>IRCT20230507058110N1, 2023-05-13.</p>