The embodiment of the invention provides a coke oven system and an operation method thereof, the coke oven system comprises a coke oven, a waste heat recovery system and a flue gas remelting system, and the coke oven comprises a carbonization chamber, a combustion chamber, a heat exchange chamber, a flue and a flue gas balance channel. Waste heat of flue gas generated by the coke oven is recovered through the waste heat recovery system, and part of low-temperature flue gas subjected to waste heat recovery is introduced into the second air channel through the flue gas balance channel by utilizing the flue gas remelting system, so that the content of oxygen in combustion-supporting air can be reduced, and when the generation amount of raw coke oven gas in the carbonization chamber is increased, the content of oxygen in the combustion-supporting air is reduced. According to the invention, less oxygen and raw gas can be combusted, so that the phenomenon that the local temperature of the coke oven body is too high is avoided, the combustion state in the vertical flue of the coke oven is stabilized, the heating uniformity of the coke oven is improved, and the safety and stability of a coke oven system are further improved.