Investor trading behavior is shaped by emotions and individual belief systems, with fear and greed being among the most significant factors influencing trading decisions in the capital market. In this context, religious orientation—as part of an individual's value system—can influence emotional control and the decision-making process. This study aims to examine the impact of individual investors' religious orientations on trading behaviors driven by fear and greed in the Tehran Stock Exchange. To this end, data were collected from 384 active individual investors using Allport’s Religious Orientation Scale and a researcher-developed questionnaire regarding fear- and greed-driven trading behavior. The sample size was determined using Cochran’s formula for an infinite population, and participants were selected via convenience sampling. The validity of the instruments was confirmed through content validity assessment, while reliability was verified using Cronbach’s alpha coefficient. Data analysis was conducted using Spearman’s correlation test and structural equation modeling (SEM) with SPSS and SmartPLS software. The results indicated a significant negative relationship between investors' intrinsic and extrinsic religious orientations and trading behaviors driven by fear and greed; specifically, higher levels of religious orientation were associated with a reduction in such trading behaviors. The study’s innovation lies in the simultaneous and independent examination of the roles played by these two dimensions of religious orientation in explaining the fear- and greed-driven trading behaviors of individual investors in the Iranian capital market—a topic that has received limited attention in domestic research.