This research examined the relationship among investor psychology, herding behavior and investment performance. Four hypotheses were tested using survey data collected from 250 individual investors in Vietnam stock markets. The findings showed that core self evaluations are positively related to herding behavior. In addition, extraversion is also found to be related to herding behavior. Moreover, cognitive dissonance is also positively related to herding behavior. Finally, the result showed no significant relationship between herding behavior and individual investor performance.

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