The previous studies show that there were some drawbacks in children's pain management and the present research aims to outline the effect of two training methods (lecture and multimedia) on knowledge, attitude and performance of the nurses to manage children's pain. At first, by reviewing the literature, the available specialized references and the academic papers by library and field studies, producing multimedia program (producing text, film with sound and animation) for training the intervention group nurses is done through designing and programming coordinated by two IT experts by FLASH or ISpring Suite 7 software, we will be assessed the software, by 10 multimedia design theoretical principles of Mayer criteria with checklist. After the informed consent being completed, 100 of nurses affiliated to 17-Shahrivar hospital of Rasht, will be selected, who eligible to enter the study, they will answer the questions on the demographics, performance, knowledge and attitude questionnaires. Then according to knowledge scores level, the participants will randomly be divided into two groups of intervention ( multimedia training) and control (lecture based training ) and will be exposed to the training methods during a 6 h session as 4 h theoretical and 2 h practical through being invited by the nurses, one week and a month after the training ,both groups will be given the 1st and 2nd post-tests using the same questionnaires, and via the basic scores adjustment, the effect of training will be compared.