Background: Marital infidelity is one of the most traumatic interpersonal phenomena that threaten the institution of couple and family, and in recent years it has become a major social harm that triggers other social harms. Therefore, preventive interventions based on scientific research can be effective in reducing the probability of this interpersonal problem. Aim: The main goal of this research is to create and validate the protocol for preventing marital infidelity and increasing marital commitment. Methodology: First, a deep and extensive review of the research literature related to marital infidelity and couple therapy was conducted using a qualitative method, in order to collect the necessary data for the development and design of the educational protocol. Based on the extracted data, a 12- session training protocol was designed and compiled with the aim of raising awareness and training individual and interpersonal skills. For the internal and content validation of the designed protocol, the Delphi method (recall from experts) was used. The selection of experts was done using a targeted and 202 available non-random sampling method. For this purpose, a researcher-made questionnaire that measured different aspects of the designed protocol was sent to the experts along with a summary of the created protocol that included the titles, goals, content and assignments of each training session. The data obtained from the validation questionnaire were analyzed quantitatively using descriptive statistics (mean and standard deviation) and calculating the content validity ratio (CVR) and content validity index (CVI). Conclusions: The designed protocol had internal validity and content from the point of view of experts in the field of couple, family and marital infidelity. Based on the results obtained, it can be concluded that this educational protocol for training and enhancing the skills of spouses and young people about to get married can be beneficial and has the nec