A 3-D finite element method (FEM) based model of the bioheat transfer equation has been developed to simulate the unsteady temperature distribution in a human head undergoing external cooling. A finite element analysis (FEA) code was developed to solve the bioheat transfer equation in arbitrary shaped 3-D multi-material objects discretized with tetrahedral elements. The correctness of the code was verified by comparing numerical results against an exact analytical solution for a simple geometry. The code was then used to simulate the unsteady heat transfer in a human head. Simulations were made with and without the effects of cold blood perfusion. Several values of arterial temperature were used for the perfusion cases.