Arun NeupaneShrestha, Ram Sundar2026-02-262026-02-262025https://hdl.handle.net/20.500.14540/25725This study aimed to investigate the connection between behavioral bias factors and investment decisions, as well as the impact of behavioral bias factors (Heuristic, Prospects, Market, Herding bias) on Nepalese share market investment decisions. This study employed a descriptive and causal comparative research design. With the use of questionnaires given to 426 investors, this study was carried out on all investors who invest in NEPSE-listed firms as a population. Data was gathered and surveyed, and descriptive statistics, correlation, and regression were used for analysis. The results of the regression analysis showed that heuristic bias was a positive and significant impact on investment decisions, as do prospect bias, market bias, and herding bias. The study offers implications for financial advisors to become more proficient, policymakers to consider biases in previous policy changes, the development of sustainable investment management methods, and individual investors to better understand their behavior. Legislators have the power to enact rules that would aid in removing investors' perceived prejudices. The biases influencing investor behavior might be found using this study by brokers. They can provide their clients with wise counsel to keep investors from making poor decisions. Keywords: Heuristic, Prospects, Market, Herding, and Investment Decision.en-USShare marketSecondary educationThesis