ObjectiveTo observe female university students' differences of cognitive mechanism in processing different types of sexual picture from International Affective Picture System (IAPS).MethodsUsing event related potential (ERP),the differences of the amplitudes of N2,P3 and PSW were examined induced by the neutral pictures and different types of erotic pictures.ResultsThe amplitudes of N2 ( (0.99 ±1.69 ) μV) and P3 ( ( 17.27 ± 1.45 ) μV) elicited by heterosexual couple erotic pictures were highest,followed by the male erotic pictures( ( -0.02 ± 1.83 ) μV,( 15.92 ± 1.26 ) μV),and then were the female erotic pictures ( ( -0.22 ± 1.56)μV,( 15.49 ±1.34) μV).There was statistical significance in N2 and P3 between heterosexual couple erotic pictures and female erotic pictures ( P ＜0.05 ).There was no significant difference in PSW component between heterosexual couple erotic pictures( ( 15.22 ± 1.98 ) μV) and female erotic pictures ( ( 14.53 ± 1.75 ) μV ),but the PSW induced by male erotic pictures (( 10.93 ± 2.60 )μV) was significantly smaller than the other sexual pictures (P＜0.05).ConclusionThe level of sexual arousal elicited by explicit heterosexual couple erotic pictures is highest and also the attention maintains longest.