The disclosure is directed to a memory storage device and an automatic error repair method thereof. In an aspect, the memory storage device includes a connection interface configured to receive a write command and a word line address associated with the write command, a memory array including a memory bank which contains an error correction code (ECC) detector, a plurality of memory cells controlled by a word line address, and a plurality of redundant memory cells controlled by a redundant word line address, a fuse blowing controller configured to receive the word line address to blow an electrical fuse of the word line address to enable the plurality of redundant memory cells, and a memory control circuit configured to transfer data from the plurality of memory cells through a bit line into the plurality of redundant memory cells in response to the electrical fuse having been blown.