The invention discloses a system for preventing unauthorized use of an IC card. The system comprises an IC card reader-writer, a microprocessor, a testing UID card, a power supply module, a display module, and an automatic alarming device. The device is capable of preventing the unauthorized use of the IC card mainly by determining whether the data writing-in state of the 0 block data of the 0 sector of the IC card, the number of the IC card, and information stored in the IC card are consistent with related information of a system database. The UID card is tested to determined whether the working of the system is normal. When the working of the system is normal, user IC card operation is carried out. When the IC card is not the original card, the system is capable of forbidding the writing and reading operation of the card, and is used to transmit IC card leakage prompting information to a cell phone of a user and a public security organ by short messages. The principle and the operation of the device for preventing the unauthorized use of the IC card are simple and clear, and therefore whether the IC card information is leaked can be determined accurately, and the safety and the confidentiality of the IC card are greatly improved.