BackgroundThe use of preventive behaviors of musculoskeletal disorders (MSDs) requires proper training, which leads to correct decisions regarding maintaining postures at work and performing stretching exercises. Due to very repetitive work, applying manual force, improper postures, and static contractions of proximal muscles, assembly-line female workers suffer from musculoskeletal pains. It is assumed that structured and theory-based educational intervention using a learning-by-doing (LBD) approach may increase the preventive behaviors against MSDs and reduce the consequences of these disorders.MethodsThis randomized controlled trial (RCT) will be conducted in three phases: phase 1: validation of the compiled questionnaire, phase 2: determining the social cognitive theory (SCT) constructs that predict the preventive behaviors of MSDs in assembly-line female workers, and phase 3: designing and implementing the educational theory. The educational intervention is based on the LBD approach, and the study population includes assembly-line female workers in electronic industries of Iran, who are randomly divided into two intervention and control groups. The intervention group received the educational intervention in the workplace and the control group does not receive any intervention. The theory-based educational intervention includes evidence-based information along with pictures, fact sheets, and published literature about a good posture at work and the need to perform proper stretching exercises. The educational intervention aims to improve the knowledge, skills, self-efficacy, and intention of assembly-line female workers to adopt preventive behaviors of MSDs.DiscussionThe present study will evaluate the effects of maintaining a good posture at work and performing stretching exercises on the adherence to preventive behaviors of MSDs among assembly-line female workers. The developed intervention is easily implemented and evaluated in a short period of time based on the improved score of the rapid upper limb assessment (RULA) method and the mean score of adherence to stretching exercises and can be provided by a health, safety, and environment (HSE) expert.Trial registrationClinicalTrials.gov IRCT20220825055792N1. Registered on 23 September 2022 with the IRCTID.