The pressure drop across "Higee", a synonym for high-gravity technology, is one of the most important characteristics, and the liquid flow gives rise to intriguing and unusual effects on the pressure drop. The pressure drop of the wet Higee can be substantially lower than that of the dry one. This trend is quite different from the conventional packed and trayed tower. And the unusual effects also occur in the rotating zigzag bed (RZB), a novel type of Higee. The pressure drop of RZB was studied by two methods of the pressure drop model, based on gas tangential velocity and empirical correlation. By use of an air-water system, experiments were carried out in a RZB with a rotor that had an inner diameter of 214 mm, outer diameter of 486 mm, and axial height of 104 mm. The radial distribution of gas tangential velocity in the RZB rotor was measured by a five-hole pitot probe. Lliquid flow reduced the gas tangential velocity due to the drag exerted by liquid droplets on the gas. The gas tangential velocities were correlated by an empirical equation on which the centrifugal pressure drop was predicted accurately. The correlation of the frictional pressure drop was subsequently obtained. As a result, the pressure drop model based on gas tangential velocity was established, from which the phenomenon that the wet rotor pressure drop is lower than the dry rotor pressure drop was reasonably explained. The rotor and overall pressure drops of RZB were correlated by empirical equations with good agreement. Deviation of the rotor pressure drops based on experiments and on gas tangential velocity was less than that based on experiments and on empirical equations. Variation of the overall pressure drop of RZB was similar to that of the rotor pressure drop. The pressure drop model based on gas tangential velocity can also be applied to the conventional rotating packed bed, which is beneficial to the theory of the pressure drop of Higee.