A hybrid numerical model for the simulation of Magnetic Force Microscopes (MFM) is presented. Furthermore, to describe the mechanical behavior of the MFM cantilever difierent kinds of force calculation methods are considered and compared to each other with respect to the total force as well as to the force distributions. In recent years a rapid miniaturization of integrated devices and data storage media is noticeable. In this regard, high resolution measurement techniques have been developed, which fulflll the in- creasing requirements for device error analysis. One of these highly sensitive measuring instruments is the Magnetic Force Microscope (MFM), which reveals the magnetic properties of an arbitrary sample. During the measurement process a micro-mechanical cantilever, which holds a magnetic coated tip underneath, is moved over a magnetic fleld inducing sample surface. Due to the magnetic interactions attractive or repulsing forces act on the cantilever and cause a de∞ection, which can be detected by a re∞ected laser beam focused onto a photodetector. Thereby it is possible to image the magnetic domain structures and hence to draw conclusions about the sample magnetizations or currents. Due to difierent error sources, as for instance a tip asymmetry or a heterogeneous tip coating as well as occurring di-culties in the investigation of soft magnetic sample materials, it is useful to support the laboratory measurements with theoretical considerations. The simulation of such a microscope can be divided into two parts, the electromagnetic and the mechanical behavior of the magnetized tip and the cantilever. In this work a three dimensional numerical MFM model is presented, which deals with the description of the electromagnetic behav- ior. Due to the immense difierences in size between the single components inside the microscope, which are most extensive between the apex radius of the magnetic coated tip and the length of the cantilever (10nm versus 200m), the FEM cannot conveniently be applied for the discretization of the whole considered calculation domain. Therefore, for this multiscale problem the considered domain is enclosed with boundary elements. This FEM-BEM coupling is necessary for a precise and e-cient calculation of the magnetic interaction flelds. In order to simulate an overall MFM scanning process and the involved cantilever de∞ection, it is essential to compute the resulting forces acting on the cantilever. For this purpose difierent kinds of force calculation methods, i.e., equivalent sources methods, the Maxwell stress tensor and the virtual work principle are implemented and compared with each other. Each of these methods is applicable for the total force calculation of a body. However, in the case of permanent magnetic materials the local force distributions strongly difier from each other (1), which has an impact on the material deformation (1,2). Hence, considering a following structural analysis of the cantilever de∞ection, appropriate physical local forces on the magnetic coated tip are required. For this reason, the virtual work principle is furthermore implemented in such a manner as reported in (3) in order to obtain the applicable local interaction forces between the tip and the magnetic inducing sample. 2. HYBRID NUMERICAL MODEL For the simulation of a magnetic force microscope difierent kinds of fleld sources and efiects have to be considered. Beside the tip magnetization, sample currents as well as sample magnetizations are possible sources for the magnetic interaction between the sample material and the microscope tip. Furthermore, the sample material under investigation could be nonlinear or even features a hysteresis. Another di-culty is the above mentioned difierence in size of the calculation domain. In order to overcome all these requirements the considered domain is decomposed into two parts