A data transmission method and apparatus for a data service includes detecting transmission states of all established packet data protocol (PDP) links, and when it is found that a first PDP is abnormal, establishing a new PDP link based on a candidate access point name (APN), to perform data transmission for a data service corresponding to the first PDP link. When data transmission is abnormal, a new PDP link is automatically established without disrupting a previous PDP link thereby implementing PDP link switching which a user is unaware of.