Existing literature examining the challenges L2 learners face when writing academically tend to focus on the examination of their written products; few has looked into their metacognitive understanding of the nature and critical features of English academic writing. As a response, this study explored EFL students’ conception of the construct of English academic writing. Data collected from 361 university students in China, using a questionnaire developed on the basis of Snow and Uccelli’s (2009) theoretical model of academic language, were analyzed using exploratory and confirmatory factor analyses (EFA & CFA). Results from EFA retained a 14-item bi-factor solution. This empirically-derived model, together with the initial 17-item four-factor theoretical model, was further tested in CFA. Results showed that the bi-factor model seemed to best explain students’ conception of this construct of English academic writing, indicating an inability among Chinese EFL learners to distinguish the four dimensions of academic language proposed in Snow & Uccelli’s (2009) model. Instead, EFL learners were only able to see academic writing as a simple combination of content knowledge and form accuracy. This discrepancy between the theoretical model and students’ working definition bears important implications for writing instruction and assessment, particularly in the EFL context.