Eight greenhouse trials evaluated the efficacy of three species of entomophilic nematodes of the genus Steinernema ( = Neoaplectana) in controlling neonate and 6-, 10-, and 14-week-old larvae of the sugarcane rootstalk borer (SRB), Diaprepes abbreviatus (L.), in sugarcane. Different densities of the nematodes Steinernema feltiae Filipjev, S. glaseri Steiner, and S. bibionis Bobien were tested. The infective nematodes controlled the 6- to 14-week-old (0.64 to 2.54 cm) larvae. Significant results were also observed on the control of the effect of the larvae on sugarcane in the various parameters measured. No significant effects were observed with neonate (first instar) larvae. Larval mortality increased with age. Eightyfive percent mortality of 10-week-old grubs was observed at 240,000 nematodes per 1.8 kg of soil with a surface area of 0.02 m. Control of 10-week-old grubs was also possible at 480,000 nematodes per 3.6 kg of soil with a surface area of 0.03 m. Fourteen-week-old grubs were the most susceptible to the attack of S. feltiae. S. glaseri is more effective than S. bibionis in controlling the grubs, but the effect of S. glaseri on the grubs is less consistent than that of S. feltiae. The three species of Steinernema performed well at temperatures of 20° to 31° C.