In order to realize the multiposition temperature accurate monitoring, wireless transmission and alarm in time, this paper designs a kind of wireless multiposition temperature monitoring and alarm system based on nRF24L01 and DS18B20. The whole system is divided into the master and the slave, which makes multiposition temperature monitoring come true by the nRF24L01 module multichannel communication controlled by STM32. The whole system hardware design and software program realization method is presented in the design. After online tested, the system is able to acquire multiposition temperature data correctly and reliably. By the low power dissipation and costeffective design ideas, the design solves the problem that the traditional routing is complex and the data transmission is unstable. Meanwhile, it has a good application value in agriculture, industry and other fields.