A method for adjusting a data packet length in near field communication, NFC, wherein the method comprises: determining, by an 2. NFC controller, 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 the NFCC is responsible for determining the maximum length value of the data packets transmitted in the subsequent communication, sending, by the NFCC, a first request comprising a first length value to a second NFC device, wherein the first request is used to instruct to adjust the maximum length value of the data packets transmitted between the first NFC device and the second NFC device in the subsequent communication to the first length value, the first request further comprises a first device identification number, DID, and the first length value is a value determined by the NFCC; receiving, by the NFCC, a first response that is returned by the second NFC device for the first request, wherein the first response comprises a second DID; and if the first DID is the same as the second DID, using, by the NFCC, the first length value as the maximum length value of the data packets transmitted in the subsequent communication; wherein the determining whether the NFCC is responsible for determining a maximum length value of data packets transmitted in subsequent communication comprises: determining whether a value of a first parameter is a first specific value, wherein the first specific value is used to represent that the NFCC is responsible for determining the maximum length value of the data packets transmitted in the subsequent communication, and the value of the first parameter is a default value of the NFCC, or a value configured by a device host, DH, of the first NFC device for the NFCC. determining, by an 2. NFC controller, 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 the NFCC is responsible for determining the maximum length value of the data packets transmitted in the subsequent communication, sending, by the NFCC, a first request comprising a first length value to a second NFC device, wherein the first request is used to instruct to adjust the maximum length value of the data packets transmitted between the first NFC device and the second NFC device in the subsequent communication to the first length value, the first request further comprises a first device identification number, DID, and the first length value is a value determined by the NFCC; receiving, by the NFCC, a first response that is returned by the second NFC device for the first request, wherein the first response comprises a second DID; and if the first DID is the same as the second DID, using, by the NFCC, the first length value as the maximum length value of the data packets transmitted in the subsequent communication; wherein the determining whether the NFCC is responsible for determining a maximum length value of data packets transmitted in subsequent communication comprises: determining whether a value of a first parameter is a first specific value, wherein the first specific value is used to represent that the NFCC is responsible for determining the maximum length value of the data packets transmitted in the subsequent communication, and the value of the first parameter is a default value of the NFCC, or a value configured by a device host, DH, of the first NFC device for the NFCC.