The invention discloses a field verification system of CTCS-4 level train control system ground equipment. The field verification system comprises a C3 interface monitoring module, a C4 interface simulation module and a C4 verification module. The C3 interface monitoring module is connected into an internal data network of the CTCS-3 level train control system ground to acquire information and transmit the information to the C4 interface simulation module and the C4 verification module. The C4 interface simulation module simulates peripheral equipment interacting with the CTCS-4 level train control system ground equipment, provides input information for the CTCS-4 level train control system ground equipment according to the information acquired by the C3 interface monitoring module and transmits information fed back by the CTCS-4 level train control system ground equipment to the C4 verification module. The C4 verification module checks the correctness of the information fed back by the CTCS-4 level train control system ground equipment on the basis of the information acquired by the C3 interface monitoring module and makes a record. By the adoption of the system, on the premise that normal operation of an existing high-speed railway line is not affected, the CTCS-4 level train control system ground equipment is verified on a field in advance, and plenty of field data are acquired for operation of a CTCS-4 level train control system.