This study proposed a set of measures for assessing noun phrase (NP) complexity in second language (L2) Chinese writing and compared the predictive power of these measures for L2 Chinese writing quality to that of a set of syntactic complexity measures based on the topic-comment unit (TC-unit). Our data consisted of 101 narratives written by beginning-intermediate, intermediate-advanced, and advanced Korean Chinese-as-a-second-language (CSL) learners and rated by 2 trained CSL teachers. Results showed that the NP complexity measures explained a substantially larger proportion of variance in holistic writing scores than the TC-unit-based measures. Our findings confirmed the validity of the NP complexity measures we proposed and the need to attend to phrasal complexity in assessing L2 Chinese writing quality.