An alarm device for a clutch that issues an alarm indicating a lifetime expiration of the clutch that selectively connects and disconnects an input shaft to and from an output shaft, includes: a slip heat release threshold setting unit 104 that establishes a threshold criteria as to a clutch damage or the clutch lifetime, in a form of a relation between a heat release generated in a clutch slip operation and a frequency of the heat release occurrences; and a slip heat release calculator 105 that calculates the heat release during the clutch operation, based on a hydraulic oil pressure in an actual clutch operation and a relative circumferential speed between input and output shafts, the alarm device 11 issues the alarm based on the calculation result through the slip heat release calculating means 105 and the slip heat release threshold setting means 104.