The invention discloses a flow-limiting valve seat of a high-pressure pump. The flow-limiting valve seat comprises a valve seat body. Liquid inlet channels are formed in the two sides of the valve seat body. One end of each liquid inlet channel is obliquely arranged, a conical opening is formed in a liquid inlet of each liquid inlet channel, and the bottom of each conical opening communicates with the corresponding liquid inlet channel. The two sides of each liquid inlet channel are further provided with flow-limiting chambers. The end, connected with the corresponding liquid inlet channel, of each flow-limiting chamber is a water inlet. Each flow-limiting chamber is internally provided with a buoy block, wherein a lug is arranged at the upper end of the buoy block and correspondingly clamped onto the corresponding water inlet. A water drainage channel is formed in the center of the valve seat body. In this way, the stability of the valve seat of the high-pressure pump can be improved, flow-limiting treatment can be carried out in time when high-pressure water flow spills into the liquid inlet channels of the valve seat, and the situation that the liquid inlet channels are impacted and damaged by the water flow is avoided; and when rapid water flow enters the liquid inlet channels, the buoy blocks in the flow-limiting chambers float to eject the lugs into the liquid inlet channels so that the liquid inlet channels can become narrow and play a flow-limiting role.