To provide a management system for lease machinery managing operating hours along with dates by means of the sending and receiving of mail and use of memory cards, thus grasping the condition of the lease machinery and charging for it in a normal way through self-management without requiring declaration.

Each piece of rental machinery is mounted with a recording device for operating hours with dates and a memory card is set therein at the time of leasing. The times and dates when operation starts and stops are stored in the memory card and the data are processed at the end of rental of the rental machinery by means of a memory card reader and a personal computer to produce a bill. In the case of a management system that relies on the sending and receiving of mail, when each piece of machinery is leased, information on the start and stop of operation and the occurrence of trouble is reported to the leasing company by use of a communication function, so the data are processed using a personal computer to inspect the machinery as well as to plan repair and produce bills. The management system for the operation of rental machinery allows the leasing company to perform self-management of each piece of machinery which it owns, thus enhancing management and operation.