The present study aims to build a model of second language (L2) reading, taking into account working memory capacity and first language (L1) literacy as variables within structural equation modeling (SEM). In this study, a total of 120 Japanese L1 high school students were given a series of tests: 1) English reading span tests, 2) English vocabulary size tests, 3) English grammar tests, 4) Japanese literacy tests, and 5) two kinds of English reading tests. One of the English reading tests was on a general topic, and the other required specific background knowledge to control for the effects of topic familiarity. SEM revealed that L2 working memory, L2 grammatical knowledge, and L2 vocabulary knowledge significantly predicted general L2 reading, while general L2 reading, along with L1 literacy, was the significant predictor of L2 reading on a specific topic. Furthermore, L1 literacy predicted L2 vocabulary knowledge, and skilled L1 readers excelled at creating situation model for L2 reading comprehension, even when they lacked topical knowledge. The present study presents a more refined model of L2 reading comprehension, which accounts for L1 literacy and working memory more comprehensively than previous research has.

e present study develops group-format reading span tests RSTs of Japanese and English for Japanese high-school students and investigates whether it is feasible to administer the tests to groups within reasonably short periods. Reliability coe cients for the newly-developed RSTs were high; for Japanese, α .864 and for English, α .875. Moreover, test scores were found to be normally distributed. ese ndings indicate that the RSTs are e ective for group administration. Further analyses of correlation di erences between JapaneseEnglish RST scores found correlation coe cients of .677 and .531 for higher English-pro ciency and lower English-pro ciency students, respectively, while a prior study has reported a correlation coe cient of .84 for English-major students. ese ndings suggest that working memory in L2 reading functions more similarly to L1 reading when L2 pro ciency is higher.