In recent years, there has been an upsurge of interest in the use of computer technologies for L2 writing instruction. Many researchers have empirically investigated the effects of the applications of educational technologies on language learners' writing performance and have highlighted the effectiveness of the use of educational technology in writing classes (Howell et al., 2021; Lan et al., 2019; Rahimi & Fathi, 2021). The aim of the present meta-analysis was threefold: (1) to examine the overall effectiveness of the applications of educational technology on English as a Second/Foreign Language (EFL/ESL) writing performance, (2) to investigate the substantive factors leading to between-study variation, and (3) to provide a genre-specific technology analysis. Sixty-four studies meeting the inclusion criteria were synthesized in this review. The results revealed that the applications of technology produce a large positive effect (g = 1.00) on EFL/ESL learners' writing performance. Moderator analyses, which were conducted with some study features, also led to the identification of two statistically significant moderator variables, i.e., genre of writing and type of technology. The results of meta-regression showed that there is a significant relationship between type of technology, genre of writing, and the overall effect size of the applications of educational technology. Pedagogical implications are discussed, and the future prospects for the use of technology-enhanced language learning (TELL) in the area of ESL/EFL writing instruction are presented.