the purpose of this study is to determine items which have differential item functioning (DIF) in TIMSS 2011 mathematics subtest with three different item response theory (IRT)- based DIF methods and compare results of these methods. For this purpose, DIF values obtained by Lord's Chi-Square , Raju's area and Likelihood-Ratio test methods were compared with respect to gender (males were the reference group while females were the focal group) to test whether procedures yielded similar results.