Pseudantechinus macdonnellensis has a wide distribution within the arid zone of Australia. Observations have been made on reproduction in both newly captured and laboratory-maintained animals obtained from widely separated localities. They have a short annual breeding season; animals from the more westerly part of the range breed later in the year. Males are potentially capable of breeding in at least three seasons, and females in at least four. Females are monoestrous and the gestation period, timed from mating to birth, is from 45 to 55 days. The young are suckled for about 14 weeks in the laboratory and are capable of breeding in the season following that in which they were born, when they are approaching 1 year of age.