The present work is devoted to theoretical vibration analysis of a complex mixed continuous system. Undamped free transverse vibrations of an elastically connected beam-string system are considered. Solutions of the problem are formulated by using the modal expansion method. Two infinite sequences of the natural frequencies cot-responding to two possible kinds of vibration motions: synchronous and asynchronous are determined. In a numerical example. illustrating the theory presented. the effect of string tension force on the natural frequencies of the system is investigated in detail. (C) 2002 Elsevier Science Ltd. All rights reserved.