GTPase immune-associated protein 5 (Gimap5), a key factor in maintaining T cell homeostasis, plays important roles in immune and inflammatory processes. However, its function and characteristics in poultry have not been reported. In this study, AA+ and Sanhuang broilers were used as models. The full-length coding sequence of the Gimap5 gene was cloned by RT-PCR and analyzed using bioinformatic methods. Tissue expression and distribution characteristics of the Gimap5 gene and its functional characteristics in inflammatory response were analyzed by RT-qPCR, respectively. The full-length coding sequences of the Gimap5 gene from AA+ and Sanhuang broilers were 771 bp, encoding 256 amino acids, and presented low conservative among different species. The AIG-1 domain of N-terminal and alpha-helix structure of C-terminal transmembrane sequence of might play important roles in the Gimap5 protein function and cell localization, respectively. The Gimap5 gene was widely distributed and expressed in various tissues and the pattern of its expression change was basically similar between AA+ and Sanhuang broilers. However, there were some differences in expression activity between the two breeds or various tissues of the same breed. In inflammatory response, the expression activities of the Gimap5 gene were down-regulated in blood and liver (P<0.05), but up-regulated in the bursa of Fabricius (P<0.01). It is speculated that Gimap5 is a multifunctional gene involved in the development of the body and inflammatory response, and has potential application value for diagnostic marker of inflammatory response.