Reading is by far the most important of the four skills in second language learning, particularly in English as a second or foreign language. Therefore, improving the English reading comprehension ability is a vital task for the EFL/ESL learners. Many researches have been made to find the different factors that influence the reading comprehension ability.The present study focuses on the relationship between English and Chinese reading ability under the framework of two hypotheses: the Linguistic Threshold Hypothesis (LTH) and the Linguistic Interdependence Hypothesis (LIH) in the EFL context. It attempts to explore the nature of language threshold, and also the nature of Chinese reading ability transfer to English reading ability when a specific level of English is achieved and also uncover other variables affecting the English reading.In the analysis multiple regression analysis is applied, in addition the subjects are divided into nine subgroups for further analysis. The results indicate that both Chinese reading ability and English language proficiency are significant predictors of English reading ability; vocabulary knowledge is the critical factor in the language threshold; when a specific English level is achieved, the relative importance of Chinese reading comprehension increases; summarizing and drawing inferences skills in Chinese and English are closely related. Results of the analysis for the questionnaire demonstrate that reader purpose and reader motivation also play an important role in improving of English reading ability. Finally, some pedagogical implications are suggested.However, there are still many questions remaining to be explored. Since research in this field has to take a multi-factor approach by operationalising conceptually complex variables, this present study can only add evidence for the research in this field.