The invention discloses a continuous circulation drilling technology suitable for gas-liquid two-phase flow drilling. The technology comprises a gas injection unit, a safe pressure relief mechanism, a gas-liquid mixing device and a gate valve control system; and the gas injection unit, the safe pressure relief mechanism, the gas-liquid mixing device and the gate valve control system are connected in sequence in operation. Then, a main circulation channel leaded out from the gate valve control system is connected into a vertical pipe, a collateral circulation channel with a pressure gauge is connected to a drill stand for future use, and a pressure relief channel is connected to a circulation tank. In normal drilling operation, a gas phase and a liquid phase are evenly mixed through the gas-liquid mixing device to enter the gate valve control system for circulating through a main circulation channel; and in single connection or round trip, a gas-liquid two-phase flow enters a drill for circulating through the gate valve control system by the collateral circulation channel. The technology solves such problems as great underground pressure fluctuation, low drilling efficiency and blockage of drilling due to fall back of chips caused by stop of single connection and round trip circulation in the large effluent stratum gas-liquid two-phase flow drilling process, and largely improves the gas drilling efficiency and safety.