While the typology of paraphrasing revolves around linguistic changes of paraphrasing, little is known about the importance of different types of linguistic changes and their relationship between paraphrasing performance and L2 proficiency. Empirical enquiry has focused on L2 writers' inappropriate paraphrasing performance against the norm of L1 writer, which is problematic in that L2 and L1 writers displayed considerable variation in paraphrasing. The present study drew upon 202 Chinese EFL writers' written responses in a paraphrasing test to look into the discrete linguistic transformations in paraphrasing and examine how the frequency of different linguistic changes in paraphrasing relates to their paraphrasing performance and L2 proficiency. Correlation analysis was run to analyze the relationship between the frequency of linguistic changes and paraphrasing performance. Multivariate analysis of variance analysis was conducted to examine how the frequency of linguistic changes relates to L2 proficiency. The findings revealed that Conceptual Transformation had the highest significant correlation with paraphrasing scores, followed by Lexical Transformation and then Syntactic Transformation. The frequency of Synonym Substitution, Morphology, Multiple Word Units, Phrase/Clause Shift, Active/Passive Shift and Conceptual Transformation increased as L2 writers' proficiency levels increased. Implications are drawn from the findings for paraphrasing instruction and assessment, research in paraphrasing and L2 writers' academic writing practice.