Reproductive (sexual dimorphism, reproductive maturity, reproductive cycle, recruitment and fecundity), feeding biology (diet composition and frequency of food items) and morphology data (body size and tail breakage) of Dendrophidion dendrophis are presented, based on the analysis of 95 specimens (61 males and 34 females) from different regions of Brazilian Amazon. There were no significant differences in the snout-vent length and tail length between males and females. Males reach reproductive maturity with a smaller snout-vent length than females, which become sexually mature when they reach approximately three times the size of the newborns. A positive, yet only slightly significant, relationship was observed between the number of vitellogenic follicles and eggs and the snout-vent length of the females. Reproductive activity occurs throughout the year, suggesting aseasonal breeding for the species. The high incidence of broken tail or visible rupture points in mature and immature males and females corroborates the hypothesis of tail breakage as a defense mechanism in this species. All food items found were frogs of the subfamily Leptodactylinae (family Leptodactylidae), most often from the genus Adenomera, followed by Physalaemus, suggesting that D. dendrophis is primarily terrestrial and anurophagous.