Filamentous fungi are efficient cell factories in producing industrial enzyme products as the efficiency in extracellular proteins secretion. Most researches on extracellular proteins secretion in new century found that the protein secretion pathway of filamentous fungi had an efficient secretion mechanism compared with other eukaryotes'. In order to explore the efficient mechanism, this paper summarized the latest research progresses of secretory pathway in filamentous fungi. The key proteins in the secretory pathway were selected to perform sequence alignment and structure alignment. And the possible efficient secretion mechanism was put forward.