This study reports on English-as-a-foreign-language teachers' beliefs about coursebooks and their adaptation profiles; it also unveils the demographic characteristics that differentiate the profiles. Responses from 3654 Chinese English-as-a-foreign-language teachers were analyzed using Latent Profile Analysis, descriptive statistics and Scheffé's method. Results indicate four distinct coursebook adaptation profiles: Highly Active, Moderately Active, Lowly Active and Adding-Deleting-Oriented. The four profiles differed significantly in the distribution of teachers by professional titles, administrative posts, types of students they teach, and participation in coursebook writing and coursebook use training. The teachers tended to regard coursebooks as resources rather than scripts.