This paper investigates the use of lexical bundles in Chinese students' academic writing across different levels of studies at an English medium university. Frequency-based bundles were retrieved from a corpus of student academic texts written at four points of time between Year 1 and Year 4, and the structures and functions of the bundles were analysed to reveal the developmental patterns in bundle use. The analysis shows that, overall, students used more types of bundles when they progressed to the higher level of studies, but there were differences in the use of preferred structural forms. The analysis also suggests a developmental order of bundle use in L2 students' academic writing: clausal and nominal bundles appeared to be acquired prior to prepositional bundles. In terms of functional distributions, discourse organizing bundles were much more prevalent than stance and referential expressions in student writing at all levels of studies, particularly in final year project dissertations. The findings indicate a linkage between levels of academic studies and the patterns of bundle use in student writing, as well as the effects of EAP instruction on the learning of lexical bundles by Chinese student writers at an English medium university in China.