The system searches out relevant documents of gene to be searched through following devices and steps: computer of having input function and display terminal, database of docuterm for document composed of database of gene name, database of word frequency base value, character-string database and database of assistant docuterm, as well as public database of biomedicine document entered through network server. The method includes following steps: carrying out analysis of word frequency, picking out keywords of gene; through professional process, building list of word frequency; finally, searching out information of gene relevant to specific function through cluster analysis. Features are: accurate positioning, searching in quick speed, avoiding rehandling so as to save human and material resources greatly, and suitable commercial development.