In order to address the needs of the continually growing number of Chinese language learners, the present study developed and presented initial validation of a 100-item Chinese vocabulary proficiency test (CVPT) for learners of Chinese as a second/foreign language (CS/FL) using Item Response Theory among 170 CS/FL learners from Indonesia and 354 CS/FL learners from Thailand. Participants were required to translate or explain the meanings of the Chinese words using Indonesian or Thai. The results provided preliminary evidence for the construct validity of the CVPT for measuring CS/FL learners' receptive Chinese vocabulary knowledge in terms of content, substantive, structural, generalizability, and external aspects. The translation-based CVPT was an attempt to measure CS/FL learners' vocabulary proficiency by exploring their performance in a vocabulary translation task, potentially revealing test-takers' high-degree vocabulary knowledge. Such a CVPT could be useful for Chinese vocabulary instruction and designing future Chinese vocabulary measurement tools.