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Many core components of the microRNA pathway have been elucidated and knowledge of their mechanisms of action actively progresses. In contrast, factors with modulatory roles on the pathway are just starting to become known and understood. Using a genetic screen in Caenorhabditis elegans, we identify a component of the GARP (Golgi Associated Retrograde Protein) complex, vps-52, as a novel genetic interactor of the microRNA pathway. The loss of vps-52 in distinct sensitized genetic backgrounds induces the enhancement of defective microRNA-mediated gene silencing. It synergizes with the core microRNA components, alg-1 Argonaute and ain-1 (GW182), in enhancing seam cell defects and exacerbates the gene silencing defects of the let-7 family and lsy-6 microRNAs in the regulation of seam cell, vulva and ASEL neuron development. Underpinning the observed genetic interactions, we found that VPS-52 impinges on the abundance of the GW182 proteins as well as the levels of microRNAs including the let-7 family. Altogether, we demonstrate that GARP complex fulfills a positive modulatory role on microRNA function and postulate that acting through GARP, vps-52 participates in a membrane-related process of the microRNA pathway., Author Summary The microRNA pathway is a post-transcriptional gene regulatory system that uses small non-coding RNAs called microRNAs to control multiple developmental and physiological processes. With the goal of unveiling factors modulating this regulatory pathway, we have undertaken the exploration of genetic interactors in the roundworm Caenorhabditis elegans. We identify vps-52, a component of the Golgi Associated Retrograde Protein or GARP complex, and establish that this complex executes a positive modulatory role on microRNA activity. The absence of vps-52 function exacerbates diverse microRNA-related defects. Molecularly, this effect relates to decreased abundance of microRNAs and the GW182 proteins. Considering that GARP is involved in the traffic of vesicles from endosomes back to the Golgi apparatus, we propose that GARP facilitates a membrane-related process of the microRNA pathway.