Stabilizer hydraulic system and heading machine

The invention provides a stabilizer hydraulic system and a heading machine. The stabilizer hydraulic system comprises a hydraulic pump, a three-way pressure reducing valve, a mode switching valve, a main reversing valve, a rodless cavity hydraulic flow direction control valve, an oil cylinder, a rod cavity hydraulic flow direction control valve, a floating valve and a propelling main reversing valve. The function of automatically switching the working mode of the stabilizer according to the current working state of the TBM can be achieved, namely, the stabilizer is automatically switched to the hydraulic spring mode during tunneling and automatically switched to the high-pressure tight supporting mode during step changing or shutdown, the hydraulic control mode is high in reliability, stability and automation degree, and manual switching is avoided; according to the stabilizer, the situation that the rodless cavity of the oil cylinder of the stabilizer is subjected to pressure building is avoided, meanwhile,