Fibropapillomatosis (FP) is a globally emerging neoplastic disease of marine turtles characterized by the formation of cutaneous and visceral tumours. The condition is strongly associated with chelonid herpesvirus 5 (ChHV5), a double-stranded DNA virus belonging to the family Herpesviridae. FP predominantly affects juvenile green turtles (Chelonia mydas) and has reached panzootic proportions worldwide. Environmental stressors such as pollution, habitat degradation and immunosuppression are believed to influence disease expression. Pathologically, FP is characterized by epithelial hyperplasia, dermal fibroblast proliferation and intranuclear inclusion bodies. Although natural tumour regression has been reported, severe cases lead to functional impairment and mortality. This article summarizes the pathology and pathogenesis of FP and highlights its significance in marine turtle conservation.