The invention provides a data transmission mode selection method and a data transmission control platform and system, belonging to the technical field of communication. The data transmission mode selection method provided by the invention includes the following steps: when a terminal is converted from a sleep state to a data transmission state and simultaneously transmits the same data through a LoRa channel and an NB-IoT channel, acquiring a first identifier and a sending timestamp carried by the data transmitted through the LoRa channel, and acquiring a second identifier and a sending timestamp carried by the data transmitted through the NB-IoT channel; and according to the received data, acquiring transmission channel information and the receiving time of the data and the amount of thedata that is separately transmitted by the LoRa channel and the NB-IoT channel and is received within a preset time, and generating a control signal for controlling the terminal to select the corresponding transmission channel to perform data transmission.