Research on the effects of second language (L2) listening strategy instruction (SI) has gained momentum in recent years (e.g. Vandergrift & Tafaghodtari, 2010). However, the reported results have been inconclusive and varied across studies. Synthesizing the results of quantitative research in this domain, the present meta-analysis sought to determine the overall effectiveness of L2 listening SI as well as to examine the extent to which the effectiveness of instruction is likely to vary as a function of a set of potential moderators (i.e. learning contexts, treatment types, methodological variables, and outcome measures). A comprehensive search identified 45 primary studies, contributing data from 51 independent samples on the effects of SI on L2 listening comprehension. The aggregated findings indicate a medium effect of listening SI (d = 0.69). These effects were also found to vary as a function of several moderator variables. Based on the obtained findings, L2 teachers are recommended to incorporate listening SI into L2 curricula. Pedagogical suggestions and directions for future research are provided in our discussion.