The baculovirus/insect cell expression system has promise for the economic production of complex eucaryotic proteins for use as human or animal therapeutics. In this system, the polyhedrin gene of the Autographa californica nuclear polyhedrosis virus (AcNPV) is replaced by the gene for a protein-of-interest. Spodoptera frugiperda cells, when infected with the recombinant baculovirus, express the desired protein after three days. In this work, a segregated model is presented that describes this system. The cell population consists of viable uninfected cells (X(VNI)), infected cells (X(I)), dead cells (X(D)), and total cells (X(T)) The viable infected cell population is further subdivided into cells producing virus, cells producing recombinant protein, and cells producing neither. The model is mathematically tractable, yet is sufficiently complex to describe the segregated nature of the infection process. Substrate limitations are included. Also, the model includes a decreasing specific glucose consumption rate after infection until lysis. Results suggest a metabolic-state-dependent virus infection efficiency, which has not been shown previously. Also, the glucose concentration during the protein production phase is found to be critical in sustaining synthesis. Finally, secondary infections are successfully predicted, demonstrating that the model is useful in aiding the design and optimization of large-scale systems where economic constraints are more prevalent.