The article presents a numerical analysis of an innovative method for starting systems based on high temperature fuel cells. The possibility of preheating the fuel cell stacks from the cold state to the nominal working conditions encounters several limitations related to heat transfer and stability of materials. The lack of rapid and safe startup methods limits the proliferation of MCFCs and SOFCs. For that reason, an innovative method was developed and verifi ed using the numerical analysis presented in the paper. A dynamic 3D model was developed that enables thermo-fl uidic investigations and determination of measures for shortening the preheating time of the high temperature fuel cell stacks. The model was implemented in ANSYS Fluent computational fl uid dynamic (CFD) software and was used for verifi cation of the proposed start-up method. The SOFC was chosen as a reference fuel cell technology for the study. Results obtained from the study are presented and discussed.