Abstract: Many teachers might have realized that placement of different lexical annotations at different locations in and around texts has different effects on EFL vocabulary learning. Yet, to what extent the effects exhibit themselves remains unknown. Our review of the literature shows that only a few studies have been conducted to verify the effects despite conflicting results. This study was conducted to fill this research gap. Specifically, it explored how annotation placement positions (annotation located before reading, on the margin or during reading, and after reading) affected L2 vocabulary learning in interaction activities in the context of EFL reading classrooms. An analysis of 85 valid vocabulary test papers showed that in classroom interaction activities: (1) different annotation placement positions had different influence on L2 vocabulary learning; (2) annotations placed before reading benefited L2 vocabulary learning the most; and (3) there was no significant difference of vocabulary learning in the cases of annotations situated on the margin and after reading. The article ends by discussing their pedagogical implications for vocabulary teaching and textbook compilation.