The study is an attempt to clarify how Chinese students’ English proficiency influences their communication with English native speakers. The subjects were 33 ESL Chinese students in the U.S.A. with the English proficiency measured by TOEFL, cloze test, and CHAT test (an oral test). Results of one way ANOVA and Scheffee’s test indicate that English proficiency was an obvious factor affecting the Chinese ESL learners’ choice of CS.