Background: The present study examined the validity of a university-based speaking assessment (Test of Oral Proficiency in English, TOPE for short) in mainland China. The speaking assessment was developed to meet the standards (Standard for Oral Proficiency in English, SOPE for short) set for teaching and learning of the oral English by the university. Methods: The degree of interaction among candidates in the second part of the test (Presentation and Discussion) was analyzed in terms of frequency of the language functions. These functions were reflected in the test syllabus, which was developed based on the CEFR.