A method for data transmission, a method for parameter optimization, an apparatus, and a device are provided. The method for data transmission includes: initiating, by user equipment UE, a random access request or a resource request to a network device; recording, by the UE, random access failure information or resource request failure information; and when detecting that the UE has successfully accessed the network device, sending the random access failure information or the resource request failure information to the network device, so that the network device sends the random access failure information or the resource request failure information to a network management device for parameter optimization processing.