This study aimed to investigate the effect of trust on the purchase intention of customers of small and medium-sized manufacturers located in Borazjan Industrial Park, considering the mediating role of perceived usefulness. This study is applied in nature and descriptive-survey and correlational in terms of implementation method. The statistical population of the study included customers of small and medium-sized manufacturers in Borazjan Industrial Park in 1403 and the sample size was estimated to be 384 people using the Cochran formula. Data were collected through a standard questionnaire with a 5-option Likert scale and analyzed using SPSS 25 and SmartPLS 2 software through structural equation modeling (SEM) and partial least squares (PLS) method. The validity and reliability of the measurement tool (questionnaire) were also confirmed with Cronbach's alpha and composite reliability indices. The research findings showed that trust has a positive and significant effect on customers' purchase intention. Perceived usefulness also has a positive and significant effect on customers' purchase intention. More importantly, perceived usefulness plays a significant mediating role in the relationship between trust and purchase intention. This means that trust enhances purchase intention by increasing perceived usefulness. These results emphasize that small and medium-sized manufacturers should focus on trust-building strategies (such as transparency, quality, and excellent customer service) and highlighting the tangible benefits of their products.