Available online at www.jlls.org JOURNAL OF LANGUAGE AND LINGUISTIC STUDIES ISSN: 1305-578X Journal of Language and Linguistic Studies, 18(1), 427-446; 2022 © 2022 Cognizance Research Associates - Published by JLLS. The relationship between L2 vocabulary knowledge and listening proficiency: The mediating effect of vocabulary fluency Yanli Tong a , Zuwati Hasim b 1 , Huzaina Abdul Halim c a University of Malaya, Kuala Lumpur, Malaysia Ningde Normal University, Ningde, China b University of Malaya, Kuala Lumpur, Malaysia C University of Malaya, Kuala Lumpur, Malaysia APA Citation: Tong, Y. L., Hasim, Z. & Abdul Halim, H. (2022). The relationship between L2 vocabulary knowledge and listening proficiency: The mediating effect of vocabulary fluency. Journal of Language and Linguistic Studies, 18(1), 427-446. Doi: 10.52462/jlls.192 Submission Date:05/08/2021 Acceptance Date:18/10/2021 Abstract Based on 312 samples, this study investigated the relationship between two dimensions of L2 vocabulary knowledge (VK) and listening comprehension (LC) by comparing written and oral vocabulary measurements and further examined the mediating effect of L2 vocabulary fluency (VF) by using Bootstrapping and Monte Carlo Method. Results show that: 1) the regression coefficient from written receptive breadth and depth of VK to LC were β = .29*** and β = .22***; 2) the regression coefficient from oral receptive breadth and depth of VK to LC were β = .34*** and β = .31*** ; 3) the variance explanatory power of LC reached 64%; 4) VF played a partial mediating role between VK and LC; 5) on the condition of the mediating effect of VF, regression coefficient of written receptive vocabulary breadth to LC increased by 13%, reaching β = .42***, that of oral one to LC raised by 17%, reaching β = .51***; 6) regression coefficient of written receptive vocabulary depth to LC increased by 19%, reaching β = .41***, that of oral one to LC raised by 15%, reaching β = .46***. Finally, we discussed respective importance of different dimensions of VK in LC. The conclusion of the study was of significance to teaching of L2 VK and LC. Keywords: written receptive vocabulary breadth and depth; oral receptive vocabulary breadth and depth; listening comprehension; vocabulary fluency; mediating effect 1. Introduction Vocabulary Knowledge (VK) plays a crucial role in the process of language development (Laufer, 1998; Nation, 2013; Read, 2004). Many scholars emphasize the importance for L2 learners to command sufficient VK in connection with different language skills (Laufer, 1998; Nation, 2013; Schmitt, 2010). Since VK is an important predictor of Language Proficiency (LP), research on the relationship between VK and LP has attracted many scholars locally and globally. Although previous research on the relationship between VK and reading comprehension (RC) (Cheng & Matthews, 2018; Nation, 2001; Qian, 2002, 2004) yet studies on the correlation between VK and LC are rather limited (Cheng & Matthews, 2018; Stæhr, 2008, 2009). For most studies that examined the correlation 1 Corresponding author E-mail address: zuwati_hasim@um.edu.my