A method, an apparatus, and a system are provided for adjusting a data packet length in near field communication NFC. The method includes: determining, by an NFCC of a first NFC device, whether the NFCC is responsible for determining a maximum length value of data packets transmitted in subsequent communication; if yes, sending a first request comprising a first length value to a second NFC device, the first request further includes a first DID; receiving a first response that is returned by the second NFC device for the first request and that comprises a second DID; and when the first DID is the same as the second DID, using the first length value as the maximum length value of the data packets transmitted in the subsequent communication.