The main objective ofthisstudy is to evaluatethe effect offirm size, beta, financial leverageon the performance offirms listed inTehran Stock Exchangeinfourbasic metals, petrochemicals, cementandmedicine industries. The44companiesintheperiod 2007 to 2012 have beenselected as sample in theTehran Stock Exchange. Todo study,the relationshipbetween the variables, usingthesoftwareEviews 8assessmenttest. Toestimate themodel, theF testLimerto select the bestmodel is used thecombined data. The results of this research indicate a significant and negative relationship between financial leverage on corporate performance in the industries of basic metals, petrochemical, cement, pharmaceuticals. The relationship between beta and corporate performance in Basic metalsandpetrochemicalindustries is positive and significantandnot significantinthe cement industryand medicine. The relationship betweenfirm size and corporate performancein thebasic metals, petrochemicaland pharmaceuticalindustries is positive and significant and cement industry is negativeand significant.
