The invention relates to a wireless metering method of a flow of a faucet. The metering method comprises the following steps that pressure is converted to an electric signal through an upstream pressure sensor, with an internal wireless launching device, installed at the faucet, the electric signal is sent to a collection storage by a wireless signal and then launched to a router by the wireless signal, a numerical value of the electric signal is received by a developed application program terminal, an instantaneous flow is calibrated by a weighing method or a volume method, a relationship between the upstream pressure and the instantaneous flow is established, finally, the flow of the faucet can be displayed in real time by utilizing a mobile phone or other APP application terminals, and the cumulative flow is metered by a software. The wireless metering method is used for measuring the instantaneous flow and the cumulative water consumption of the faucet, can also movably display a result in real time through the application program terminal (APP), provides support to families or plants to reasonably use a water resource, and thus reaching the purpose of saving the water resource.