The problem of optimal control of transverse rotor vibrations with gyroscopic interactions has been described and solved in the paper. An integral performance index has been defined for such system in order to minimize vibration level of a chosen rotor point. For this reason, an efficient way of establishing weight coefficients of integral performance index for multi-degree-of-freedom system with gyroscopic interactions has been described. Presented method enables to determine such weighing coefficients that selected modal forms would be assumed before dynamics properties and a performance index would took the minimum value. Computation results demonstrate that the proposed method is efficient and may be applied for complex mechatronic systems.