According to aptitude theory, the measures of aptitude include not only cognitive factors but also affective factors (i.e., emotions) and conative factors (i.e., motivation) that can influence students' learning achievement (LA). Therefore, this study employed structural equation modelling from experimental data of 96 college students to investigate the effects of affective factors and conative factors on LA using online social network (OSN) attention as a moderating factor. The results confirmed that there are significant differences between student engagement and LA for overall group and student engagement, affective scores, and LA for the high OSN attention group. There are no significant differences for the low OSN attention group. Moreover, learning achievement can better facilitate the effects of the affective and conative levels for students with high rather than low OSN attention. In conclusion, the moderation of OSN attention shows that there are relationships that differ significantly across the high and low OSN attention groups.