To predict the service life of a construction machine more accurately, and to make it possible to draw up an appropriate overhaul implementation plan at an early stage.A first service life prediction unit 311 predicts the service lives of main components such as an engine and the like, based upon their actual wear states. And a second service life prediction unit 312 predicts the service lives of the same components, based upon their cumulative load amounts. An order setting unit 320 selects the ones of these two predicted service lives which are the shorter, and sets a priority order for overhaul in order of shortness of predicted service life. An overhaul schedule table generation unit 330 creates a schedule table D1 based upon this priority order. The contents of this schedule table D1 are decided upon by a judgment unit 340, and, if necessary, are corrected by a correction unit 341. And a plan creation unit 350 creates an overhaul implementation plan document D2 and the like, based upon the corrected schedule table D1a. The result of the overhaul task and the present states of components are tested, and these test results are reflected by the service life prediction units 311 and 312.