Abstract The temperature‐dependent development rate of pupae of greyback canegrub, Dermolepida albohirtum (Waterhouse) (Coleoptera: Scarabaeidae), a major pest of sugarcane in central and northern Queensland, was determined under six constant temperature regimes: 18, 20, 23, 25, 27 and 30°C, and for four geographically separated populations. Development rate increased significantly with increasing temperature. Parameters of the linear regression equation did not differ among populations and common coefficients were calculated. Developmental zero, at and below which no development occurs, for pupae was 12.0°C and the thermal constant was 476 day‐degrees (D°). Minimum and maximum periods for pupal development were 26 days at 30°C and 75 days at 18°C, respectively. The phenology of pupae was determined in soil‐filled cubicles in a shade house and in the field at Ayr (19°35′S, 147°25′E), north Queensland, using D. albohirtum field‐collected as late‐stage third‐instar larvae and kept in containers. Pupation of D. albohirtum began in late August or early September and eclosion was complete by mid‐ to late October. The phenology data were used to validate the development model. Eclosion was predicted by summing hourly fractions of day‐degrees until 476 D° was reached and was close to actual eclosion. As temperature, and hence pupal development rate, varies with soil depth, the distribution of the third instars in pupal cells in the soil profile was determined in recently harvested fields of sugarcane in the Burdekin sugarcane district centred on Ayr. Numbers of late third instars in pupal cells peaked at 300–400 mm, with pupae found from 30 to 700 mm. Pupal development was simulated using hourly soil temperatures measured at depths of 200 and 400 mm at Ayr and at Sarina (21°22′S, 149°13′E). The pupal stage was predicted to take up to 2–10 days longer at 200 mm deep than at 400 mm depending on pupation site and date. When pupation was simulated in late August, as is likely in the field, pupal development at 400 mm deep took 48–56 days at Ayr and 58–62 days at Sarina.