The purpose of this study is to investigate behavioral finance in which the effects of finance are relatively new. Behavioral finance explores the cognitive and emotional factors affecting the decision making process of individuals, groups and organizations. It deals with the behavioral and psychological consequences of financial decisions and is a multidisciplinary subdivision of finance. In this research, individual investors are taken for sampling and the main purpose is to examine the irregular behaviors of these investors in their investment decisions and their relations with demographic variables. Snowball sampling was used for non-random sample types and an online questionnaire was applied. 13 participants were excluded from the study due to the answer to the control question and the answers of 115 participants were analyzed. The attitudes of individual investors to the dimensions of “cognitive dissonance”, “overconfidence” and “imitation and the herd behaviors” were evaluated. The frequencies, percentages and mean values of the demographic and scale questions were determined, reliability analysis (Cronbach's Alpha), normal distribution test and chi-square independence test were applied, interpretations and recommendations were made.