We report on magnetotunneling studies in a pseudomorphic In0.1Ga0.9As/AlAs/GaAs structure in a magnetic fields perpendicular or tilted to the tunneling current. In a transverse magnetic field, we have observed a shift to higher voltages and a strong broadening of reso-nant peak in I(V) characteristics. These features are explained by the action of the Lorentz force coupling the parallel and perpendicular motions. In a tilted magnetic field, we have observed structures in I(V) characteristics which corresponds to tunneling in the prewell to the midwell with non-conservation of Landau level index in good agreement with a coherent model in which the effect of the transverse component is treated in a perturbation approach.