Guanylate-binding protein 1 (GBP1) is an interferon induced protein, that belongs to the guany late-binding protein family. GBP1 is widely involved in anti-infection immune responses, anti-tumor activity and various biological reactions. Recent studies have proved that IFN-alpha, IFN-beta, IFN-gamma, IL1alpha, IL1beta, TNF-alpha and LPS can induce GBP1 expression; hence, the diverse biological functions of GBP1 have been gradually deduced and exploited. Many studies have been performed over recent years to understand the exact mechanisms that underlie the anti-infection and anti-tumor properties of GBP1. This review describes the molecular structure, biological activity, anti-infective properties and other functions of GBP1, in order to provide insights into the divergent roles of GBP1 in the regulation of various biological processes.