Ferromagnetic resonance fields in a microtube with the various ratio of the inner and outer diameter of the tube β were studied using micromagnetic simulation. For β < 0.15 the resonance field agrees with the prediction of the Kittel equation for an infinite ferromagnetic cylinder for both parallel and perpendicular orientation of the applied field to its axis. For β > 0.15 the resonance field increases from the resonance field of the infinite cylinder and approaches the level of the film magnetized along the plane. This behavior was at odds both with the prediction that can be made using analytically calculated demagnetizing factor in ferromagnetic tube, and with the prediction that use the empirical dependence of the demagnetizing field on β, established from the magnetization curves. For β > 0.15 and transverse applied field a number of resonance peaks were observed.