he primary purpose of this study was to provide validity evidence for the Vocabulary Size Test ，which is designed to measure the vocabulary size of non － English majors in universities． The preliminary test papers were established by integrating principles from literature review． After two experimental tests on students ，the final Vocabulary Size Test Paper containing 104 i- tems was produced based on their item discrimination and difficulty． Results showed: its Cronbach's coefficient was 0 ． 918; test － retest reliability was 0 ． 644 ，p = 0 ． 000 ; discrimination validity was t = 6． 358 ，p = 0 ． 000 ; Correlation coefficients between lev- els scores were from 0 ． 068 to 0 ． 496; Correlation coefficients total score and levels scores were from 0 ． 294 to 0 ． 812 ，fitting me- trology demand． The conclusion was that the Vocabulary Size Test Paper has sound psychometric properties for Chinese college students 。