The potential connection between human adenovirus type 36 (Ad-36) infection and obesity has received extensive research attentions in recent years. Studies indicated that Ad-36 antibody may be associated with body mass index (BMI) in obesity population, and the results were further confirmed in animal model and in vitro cellular models. Viral E4 orf-1 gene, cellular adipocyte differentiation pathway and phosphatidylinositol 3-kinase (PI3K) signaling pathways are current focal points of mechanism studies. Since limited data is available, more epidemiological data and mechanism studies are needed to confirm the relationship between Ad-36 infection and obesity.