The pea aphid Acyrthosiphom pisum (Harris) (Hemiptera: Aphididae) is a pestiferous species with a worldwide distribution. We investigated the development periods and survivorship of A. pisum nymph, and longevity and fecundity of A. pisum adult. The study was conducted at five constant temperatures of 10, 15, 20, 25, and 30°C. Higher temperature threshold (TH) and lower temperature threshold (TL) were calculated by two nonlinear functions. The temperature range of A. pisum from TL to TH using empirical model (29.29) was wider than that using biophysiological model (21.85). The adult emergence frequency of A. pisum over full range of constant temperatures was simulated using developmental rat