The invention provides a hydrant with a water consumption monitoring function and without an externally connected power supply and a monitoring method, and belongs to the technical field of water consumption monitoring. The hydrant comprises a hydrant body as well as a solenoid valve, a hydraulic generator, a GPRS chip, a control card, a water flow sensor, a rechargeable battery and a camera whichare arranged in the hydrant body; when a hydrant switch is switched on and water flows through the hydraulic generator, the hydraulic generator is pushed to generate powder to provide electricity forthe devices, and surplus electricity is stored in the rechargeable battery; the GPRS chip transmits a water consumption signal to an SCADA system wirelessly, if the water consumption is non-planed, acommand for closing the solenoid valve is issued, the GPRS chip receives the command and transmits the command to the control card, and the solenoid valve is closed under control of the control card.The hydrant and the monitoring method solve the problem that illegal water consumption cannot be prevented in the prior art, and can be used for water consumption monitoring of an outdoor hydrant.