SUMMARY
Initial public offering is an important event in the life cycle of a company and also one of the financial phenomena that various studies and different opinions about that have been done all over the world. The purpose of this study is to evaluate the effect of conditional and unconditional conservatism at the time of initial public offering on long-term stock returns of companies listed on the Stock Exchange of Tehran. The research time territory is from 2002 to 2014, respectively. It was used of Eviews econometric software for data analysis and for hypothesis testing was used of multivariate regression model (logistic regression). The results showed no significant relationship between both conditional and unconditional conservatism in the initial public offering on long term returns of shares in companies listed on the Stock Exchange of Tehran.