This paper examines and studies the use of lexical and syntactic nominalizations in the argumentative writings by Chinese EFl learners of science and engineering, with a comparison to a native English corpus. The studies find that, on the lexical level, the use of nominalizations by Chinese EFL learners tends to be inadequate as well as excessive. High frequency of repetition leads directly to the excessive use of normalizations; on the syntactic level, the normalizations realized by Wh- clauses are overused, while Adj.+ Prep.+ V-ing structures are underused. The qualitative analysis reveals that only a handful of Chinese EFL learners of science and engineering can use nominalization properly whereas a majority of them do not realize the active functions of normalizations, the consequence of which is a lack of coherence, an element of subjectivity and a distinct oral style in their writing.The findings of the study may contribute to English lexical and writing teaching of science and engineering students in China.