A Hybrid Automatic Repeat request, HARQ, data storage management method, operating in Long Term Evolution, LTE, or 5G system, applied to an HARQ data cache, the method comprising: receiving operation control information when performing first transmission or retransmission based on an HARQ, wherein when performing the first transmission or non-last retransmission based on the HARQ, the received operation control information comprises a write command and write data, and the write data received each time is HARQ data incorrectly decoded; when performing the first retransmission or the non-last retransmission based on the HARQ, storing the write data according to the write command, wherein when the non-last retransmission is performed based on HARQ, the received operation control information further comprises a read command; when the last retransmission is performed based on the HARQ, the received operation control information is a read command; accordingly, the method further comprises: when the retransmission is performed based on the HARQ, reading HARQ data according to the read command; characterized in that, the HARQ data cache comprises a plurality of Cache Line for storing HARQ data; accordingly, the step of reading the HARQ data according to the read command comprises: when a read hit is determined according to the read command, reading HARQ data from a Cache Line corresponding to the read command; marking data stored in the Cache Line corresponding to the read command as invalid, or releasing data stored in the Cache Line corresponding to the read command; when a read miss is determined according to the read command, reading the HARQ data from the external memory according to the read command. receiving operation control information when performing first transmission or retransmission based on an HARQ, wherein when performing the first transmission or non-last retransmission based on the HARQ, the received operation control information comprises a write command and write data, and the write data received each time is HARQ data incorrectly decoded; when performing the first retransmission or the non-last retransmission based on the HARQ, storing the write data according to the write command, wherein when the non-last retransmission is performed based on HARQ, the received operation control information further comprises a read command; when the last retransmission is performed based on the HARQ, the received operation control information is a read command; accordingly, the method further comprises: when the retransmission is performed based on the HARQ, reading HARQ data according to the read command; characterized in that, the HARQ data cache comprises a plurality of Cache Line for storing HARQ data; accordingly, the step of reading the HARQ data according to the read command comprises: when a read hit is determined according to the read command, reading HARQ data from a Cache Line corresponding to the read command; marking data stored in the Cache Line corresponding to the read command as invalid, or releasing data stored in the Cache Line corresponding to the read command; when a read miss is determined according to the read command, reading the HARQ data from the external memory according to the read command. when the retransmission is performed based on the HARQ, reading HARQ data according to the read command; characterized in that, the HARQ data cache comprises a plurality of Cache Line for storing HARQ data; accordingly, the step of reading the HARQ data according to the read command comprises: when a read hit is determined according to the read command, reading HARQ data from a Cache Line corresponding to the read command; marking data stored in the Cache Line corresponding to the read command as invalid, or releasing data stored in the Cache Line corresponding to the read command; when a read miss is determined according to the read command, reading the HARQ data from the external memory according to the read command. when a read hit is determined according to the read command, reading HARQ data from a Cache Line corresponding to the read command; marking data stored in the Cache Line corresponding to the read command as invalid, or releasing data stored in the Cache Line corresponding to the read command; when a read miss is determined according to the read command, reading the HARQ data from the external memory according to the read command.