In an intravenous anesthesia, the Bispectral Index (BIS) is a reliable index to anesthetic depth. We developed an intravenous anesthesia control system using a model predictive controller based on BIS. Also, we developed an on-line identification method of pharmacodynamics and delay time for each patient, because the individual differences of the responses of BIS to anesthetic drug are very large. However, it is not easy to design the model predictive controller so that specified amounts of delay and gain margins are guaranteed. In this paper, an intravenous anesthesia control system using a state-predictive controller, for which a theoretical method is available to assure delay and gain margins, is developed.