Assessment literacy has emerged as an important research field during the past decade, yet it remains a great challenge for secondary school EFL teachers in China to appropriately enact their assessment literacy. Due attention needs to be paid to research upon teachers’ conceptions of assessment (CoA) and assessment practice . Based upon a semester-long observation of the English classes in a secondary school in China, weekly meetings on English teaching and research, a focus group interview, individual interviews, documents such as the participants’ lesson plans and reflective journals, this qualitative study aims to explore: (1) what are the conceptions of assessment of the participating secondary EFL teachers? (2) what are their assessment practices? (3)which aspects of their teacher assessment literacy need further enhancement?