The L2 Motivational Self System (L2MSS) has been widely researched and used to explain L2 learners' motivational behaviors. However, important factors such as language learning anxiety, self-efficay and possible family influence need to be scrutizized in relation to L2MSS in order to expand our understanding of the second language learning process. This study used a structural eauation modeling approach to test a hypothesized model that contained the L2 Motivational Self System, family influence, L2 learning anxiety, and self-efficacy as the latent variables in a context of foreign language learning. A total of 473 Taiwanese high school students participated in the study. With Amos version 22.0, the current study analyzed the proposed model. The results assured the validity of the hyposized model among these students. This model revealed that family influence played a significant role in affecting learners' future self guides. Self guides served as a good predictor for the L2 learners' self-efficacy. In addition, the ought-to L2 self contributed to a higher level of anxiety while the ideal L2 self and L2 learning experience both lowered the level of English learning anxiety.