The main issue of this paper is to understand the relation between first language and second language literacy. To explore this, Linguistic Interdependency Hypothesis (LIH) and Linguistic Threshold Hypothesis (LTH) will be discussed as two dominant viewpoints. Both hypotheses are concerned with first language literary skills and second language proficiency respectively. The key debates are related to a) transfer of literacy skills from the first language to the second language and b) minimum level of second language proficiency is required to utilize the first language literacy skills. Further, empirical researches have been cited to provide evidence supporting the arguments. Keywords: Linguistic Interdependency Hypothesis, Linguistic Threshold Hypothesis