Various genres of textbooks have been researched from the perspective of Systemic Functional Linguistics (SFL). Although the previous research has been concerned with textbooks covering subject areas in English speaking countries, it has not examined English as a Foreign Language (EFL) textbooks. By analyzing 14 EFL textbooks for junior high school and high school students from the perspective of the SFL grammatical metaphor, this study attempts to examine levels of lexico-grammatical complexity and its sequential features as used in the data. The findings show that semantic junctions whereby semantic elements are incongruently realized at the level of lexicogrammar do not always follow grade sequences of EFL textbooks. The establishment of overall ratio of grammatical metaphorical types in the EFL textbooks in this study further provides suggestive evidence that there may be a semantic gap between standardized EFL tests and the level of textbooks used at schools.