A memory including a memory cell array, a word line decoder, a first and a second reference bit line generators are provided. The memory cell array has first and last bit lines respectively disposed at two sides of the memory cell array. The word line decoder generates a pre-word line signal. The first and the second reference bit line generators respectively detect voltage level variations of the first and last bit lines according to the pre-word line signal, so as to generate a first and a second cut-back signals. The first reference bit line generator transmits the first cut-back signal to the second reference bit line generator, the second reference bit line generator transmits the first and the second cut-back signals to the word line decoder, and the word line decoder generates a word line signal according to the first and the second cut-back signals and the pre-word line signal.