The paper describes a general methodology for the transient dynamic response of the rocket and satellite coupled system by frequency responses with rational function approxima-tions. Basing on the discrete frequency functions of the rocket and satellite respectively by finite element method, the rocket and satellite coupled model is achieved according to the continuous displacement or force equilibrium. Details and practical implementation of the method are demon-strated by a simple mass-stiffness system and a real rocket and satellite coupled model. The procedure is also shown to be advantageous for the transient dynamic response of the rocket and satellite coupled system by real measurement frequency responses characteristic.