The present laboratory experiments have been carried out to investigate rhythms in various life events, viz. mating, oviposition, hatching, moulting, pupation and eclosion, of an aphidophagous ladybird beetle, Cheilomenes sexmaculata under laboratory conditions. Incidences of mating and eclosion occurred mostly (66% and 73% respectively) in photophase. While oviposition, hatching, moulting and pupation occurred during scotophase with the peaks of the former two distributed between time intervals 12:00-15:00 h and 21:00-00:00 h respectively. Confinement of life events that are associated with vulnerable stages in scotophase might be an adaptation to prevent their exposure to natural enemies.