Abstract: The UPS (Ubiquitin Proteasome System) is a major post-translational regulation pathway in eucaryotes, allowing rapid and selective degradation of proteins. These proteins are either misfolded or damaged polypeptides (quality control), or key developmental/metabolic regulators. The latter are selectively recognized and labelled with a poly-ubiquitin chain by E3-ubiquitin ligases, prior to degradation in a large multi-subunit complex called the 26S proteasome. In plants, the UPS controls many processes, in particular most hormone signalling pathways, and several other important steps including cell cycle, shoot branching, biotic stress response and self-incompatibility. Recent data highlight that the UPS is also crucial for male gametophyte (i.e. pollen) development. Plant male gametophyte development requires several tightly regulated processes of nuclei movement, cell divisions and differentiation that are well described, but which molecular control still needs to be deciphered. Different transcriptomic data indicate that transcripts for most UPS actors are found in microspore and/or pollen cells. In the last few years, the role of several components of UPS, including proteasome subunits and proteins involved in targets recognition/ubiquitylation, has been demonstrated during male gametogenesis. In particular, the role of an F-box protein that is transiently transcribed in male germ cell and specifically required for mitosis entry, has allowed significant progress in building a model of the control of male gametophyte development. In this review, I try to state all published evidence for an implication of UPS components in male gametophyte development, and to highlight important ways that still need to be explored.