Abstract：By drawing on a socio-cultural perspective, this paper formulates a six-dimensional framework to construe the academic identity of Chinese undergraduates under English education program. This framework integrates reification and participation, two basic processes of learning based on Wenger’s community of practice. Drawing on this, an inventory for the measurement of academic identity is designed and tested. The participants are 594 third-year undergraduates who have been enrolled in English education program. The findings from an exploratory show that the academic identity of undergraduate English education program can be best construed into four factors: professional expectation, English learning, education learning and attitudinal values. But further confirmatory factor analysis indicates that the model has to be modified before good model fit indices can be obtained. Good reliability and validity of the inventory is also confirmed. This paper finally discusses the implication of this study on the theorization of identity and research on academic identity for English education program.