A high noise immunity capacitive level shifter suitable for half-bridge GaN drivers is proposed. During dV/dt transitions and ringing period of the floating power rail, the proposed level shifter adopted decoupling switches to completely eliminate the common-mode noise that interfere with output states, and adopted dynamic switches to reduce the differential mode noise caused by circuit mismatch. Moreover, high negative voltage tolerance, sub-nanosecond propagation delay, and low power consumption were achieved by adopting capacitive coupling technology. The circuit was designed in a 0.18 μm high-voltage BCD process. The simulation results show that under the level shifting of 50 V, the common mode transient immunity of the level shifter reaches 200 V/ns, the mismatch tolerance reaches 30% at 200 V/ns slew rate, the negative voltage tolerance is up to -5 V, and the average propagation delay is 0.56 ns.