The study scrutinized the interaction between reading proficiency and strategic competence via reading comprehension test performance of Iranian EFL learners. The further concern was to scrutinize the extent to which strategic competence affected the participants' test performance. The participants were 506 postgraduate students who took a reading comprehension test and answered a metacognitive strategy questionnaire successively in one session. The findings manifested that the participants at the high level of reading proficiency used metacognitive strategies more frequently than did the participants at the low and intermediate levels of reading proficiency in the test-taking setting. The findings also revealed a positive linear relationship between metacognitive awareness and the participants' test performance. The findings provide empirical evidences for the close interaction between linguistic and strategic competences, as the two major components of communicative language ability, discussed in different frameworks for language use such as Bachman's (1990) and Bachman and Palmer's (1996) frameworks. The findings revealed the necessity for designing the instructional programs focusing on both linguistic and strategic aspects of language learning in a balanced way to improve reading ability of L2 learners. The findings indicate that the true score of language learners is dependent on linguistic and strategic aspects of test-taking. Thus, the findings recommend language teachers to interpret test scores with great care to make fair decisions about the actual ability of test takers. In addition, the findings encourage curriculum planners and language teachers to design appropriate instructional materials and adapt effective teaching approaches to improve reading comprehension.