Data analysis poses a significant challenge to the large-scale proteomics studies. Based on the structured and controlled vocabularies-Gene Ontology (GO), and the GO annotation from related databases, a strategy composed of several programs and local databases is developed to identify the functional distribution and the significantly enriched functional categories of the proteomic expression profile. It would be helpful for understanding the overall functions of these identified proteins and supply the fundamental information for further bioinformatics exploration. This strategy has been successfully used in the Human Fetal Liver (HFL) proteomic research, which is available online at http://www.hupo.org.cn/GOfact/.