The invention discloses a gas boiler and solar hybrid energy heating system and a control method thereof, and belongs to the field of energy conservation and emission reduction. The system comprises aheat collector, a hot water storage tank, a first electric valve, a first heat exchanger, a ground heating system, a fourth electric valve, a boiler gas heating system and a domestic hot water supplysystem, wherein a water inlet of the heat collector communicates with a water source; a water outlet of the heat collector, the hot water storage tank, the first electric valve, the first heat exchanger and the water inlet of the heat collector communicate sequentially; the first electric valve, the fourth electric valve and the domestic hot water supply system communicate sequentially; a circulating water outlet of the ground heating system, the boiler gas heating system, the first heat exchanger and a circulating water inlet of the ground heating system communicate sequentially; and the water source, the boiler gas heating system and the fourth electric valve communicate sequentially. The system solves the problems of resource waste and poor energy-saving and emission-reducing effects of an existing hybrid energy functional system, and has the advantages of high automation degree, simplicity and reliability.