Filamentous fungi are of great economic importance in industry, agriculture and medicine. On the other hand, some of them can infect human, animals and plants which caused huge economic losses. G protein signaling pathways are conserved in all eukaryotes for the transmembrane signaling transduction. To date, in fungi, G protein signaling and its regulation have been intensively studied. It has been demonstrated that G protein signaling pathways play an important role in sense and respond to various external signals which essential for the regulation of growth, development, reproduction, pathogenesis and secondary metabolite biosynthesis. This review summarized recent advances in the understanding of the basic components and biological functions of G protein signaling pathways in filamentous fungi.