Author(s): Majid Naseri, Dr. Asghar Asadi, Dr. Seyyed Mehdi Hoseiny, Dr. Mohammad Mahmoudi

This study has evaluated earning smoothing influence on information none reliability of companies in Iran investment market and has provided new observes in influencing earning smoothing on informati on none reliability. Topic eras of study includes all food industry companies and pharmacy except investment companies. place eras of study includes all accepted companies in Tehran stock exchange and its time eras is from the beginning of 2008 to the end of 2012 in Tehran stock exchange. After data application definition and determining samples, required data has been gathered from different resources. After data accounting, variables normality and statistical analysis by multi-regression method, we achieve to the amount and direction of influence and test its meaningfulness. In general case, we conclude there is meaningful and negative relation among earning smoothing and none reliability of information of business unit. therefore, we conclude earning smoothing, none reliability of information provided by business unit would decrease .models test indicates based on ball model, kotari, and robin as a whole, net earnings of companies is conservative and based on three models, conservative character is along with decreasing information content and meanwhile, net earnings report by high conservativeness does not have more yields for investors. Key words: Earning smoothing, information none reliability, accepted companies in Tehran stock exchange