Sexual dimorphism, female reproductive cycle, fecundity, and juvenile recruitment data for Anilius scytale (Linnaeus, 1758) were obtained from 155 specimens (68 mature males, 58 mature females; 29 immatures), captured between 1971 and 2006 in eastern Amazonia, Brazil. All specimens were deposited in the herpetological collection of Museu Paraense Emílio Goeldi, Belém, Pará State, Brazil. There were no significant differences in snout-vent length between mature males and females, although mature males had a significantly longer tail. Males attained sexual maturity at a smaller size than females. Females exhibit seasonal reproduction. Developed follicles were found from the end of the dry season to the middle of the rainy season (July to December). The largest embryos were found from January to April. One female gave birth in January and apparently newborn individuals (showing a visible umbilical scar) were found in January, February, March, July, and December. We did not find any significant differences between the number of follicles and embryos, indicating that all follicles may be converted into embryos.