A data transmission method implemented by a network device includes receiving first request information from a first terminal device on a first request transmission resource, where the first request information requests to use a first data transmission resource, and the first data transmission resource belongs to periodic data transmission resources preconfigured by the network device for the first terminal device, sending first authorization response information to the first terminal device on a first authorization transmission resource, where the first authorization response information indicates that the first terminal device is permitted to use the first data transmission resource, and receiving uplink data from the first terminal device on the first data transmission resource.