This study investigates pronoun interpretation by second language (L2) learners of English, focusing on whether first language (L1) transfer and/or processing difficulty affect L2 learners' pronoun resolution. It is hypothesized that L2 learners' non-target performance in L2-pronoun interpretation is attributable to two sources. The first is the computational complexity required for pronoun resolution, as argued in L1 acquisition by Grodzinsky and Reinhart and L2 acquisition by Slabakova et al. The second is how pronoun interpretation operates in L1. The hypothesis is tested by comparing Korean and Spanish L2-English learners' interpretation of English pronouns using a Truth Value Judgment Task. Both groups had difficulty rejecting pronouns with local-referential antecedents when their proficiency levels were low. Additionally, Korean speakers showed more non-target responses than Spanish speakers due to their knowledge of pronoun interpretation in Korean. These results indicate that both L1 transfer and processing difficulty may be sources of L2 learners' non-target pronoun interpretation, supporting the hypothesis of the study.