The invention discloses a high-precision underarm electronic thermometer capable of remote monitoring. The electronic thermometer includes a temperature measuring assembly and a data receiving assembly, wherein the temperature measuring assembly includes a temperature measuring block and a detachable patch adhered thereto, the temperature measuring block is in the form of a disk and internally hasa single-chip microcomputer and a data transmission module, one side is an adhesive surface, the other side is a temperature measuring surface, the center of the temperature measuring surface is provided with a convex temperature-sensitive probe, the temperature-sensitive probe is an NTC temperature measuring probe, the temperature-sensitive probe is connected with the single-chip microcomputer,a data processing chip adopts an STM32 single-chip microcomputer, the data transmission module adopts an LORA wireless transmission module WH-L101, and the data receiving assembly is an LORA concentrator communicatively connected with the LORA wireless transmission module.