The effect of constant temperatures (5, 10, 15, 20, 25 and 30°C) on several biological parameters of Noctua atlantica (Warren), a noctuid endemic to the Azores, was studied using an artificial diet as food. At 5 and 30°C no eggs hatched. Developmental time (egg, larval, pupal and egg-to-adult) differed significantly at each temperature. Pupal weight (males and females) was significantly higher at 10°C and lower at 25°C. Adult longevity and the pre-oviposition period were longer at 10 and 15°C and differed significantly from those observed at higher temperatures. The mean number of eggs laid per female (fecundity) was significantly higher at 15°C, and lower at 25°C. Pupal weight (males and females) was positively correlated with larval, pupal, egg-to-adult developmental times and with adult longevity. Female pupal weight was also positively correlated with the pre-oviposition period and with fecundity. Temperatures ranging from 10 to 20°C are the most suitable for the development of N. atlantica, suggesting that this species is well adapted to the climatic conditions found in their natural habitat. The number of day-degrees required for the development from egg to adult emergence was 1428.57 D°, and 117.79 D° for the pre-oviposition period. Thus, N. atlantica can have two generations per year at high altitudes (550 or 800 m) in the Azores.