The invention discloses a multifunctional LDO circuit applicable to a low-power-consumption RFID reader. The multifunctional LDO circuit comprises an enable control circuit, a band-gap reference circuit, a thermal-shutdown circuit, a current-limiting protection circuit, an error magnification circuit and a compensating pipe, wherein the enable control circuit, the band-gap reference circuit, the thermal-shutdown circuit, the current-limiting protection circuit, the error magnification circuit and the compensating pipe are connected with input voltage respectively. The enable control circuit is connected with the band-gap reference circuit, the thermal-shutdown circuit and the current-limiting protection circuit, the band-gap reference circuit is connected with the error magnification circuit and the thermal-shutdown circuit, the error magnification circuit, the thermal-shutdown circuit and the current-limiting protection circuit are connected with the compensating pipe respectively, and the compensating pipe is used for outputting steady voltage. In the embodiment of the multifunctional LDO circuit, by lowering the power consumption of all sub-circuits in the multifunctional LDO circuit, the steady voltage is output and the overall power consumption of the RFID reader is lowered.