The main objective of this study was to model the factors affecting the behavioral tendency of gardeners towards selling their products directly to the processing and supplementary industries among gardeners in the central part of Kohdasht County using the developed theory of planned behavior. The statistical population included all gardeners in the central part of Kohdasht County, Lorestan Province (N=1000). Based on the Krejci and Morgan table, a sample size of 270 gardeners was selected using the stratified sampling method with proportional assignment. The data collection tool was a questionnaire, the validity of which was based on the opinions of the faculty members of Khuzestan University of Agricultural Sciences and Natural Resources, and its reliability was determined through Cronbach's alpha. On the other hand, the average variance extracted (AVE) index was used to determine the construct validity and the composite reliability index (CR) was used to determine the model reliability. The results of structural equations showed that the attitude and subjective norm variables predicted 84 percent of the changes in the gardeners' tendency to sell their products directly to processing and complementary industries. Also, based on the results obtained from the developed theory of planned behavior, the attitude variable with a direct effect of 64 percent has the greatest impact on the gardeners' tendency to sell their products directly. In this regard, it is recommended to change or improve the attitude of farmers and gardeners towards selling their products directly to these industries by raising awareness and promoting information about the types of processing and complementary industries and the dimensions of their activities.