A magnetic memory, a memory cell thereof, and a method of manufacturing the memory cell are provided. The memory cell of the magnetic memory includes a bottom contact layer, a bit line, a magnetic stack structure and a dielectric material. The bit line is disposed over the bottom contact layer. The magnetic stack structure is disposed between the bottom contact layer and the bit line. The dielectric material at least fills between the bottom contact layer and the bit line and surrounds the magnetic stack structure. A gap is formed between the dielectric material and the magnetic stack structure. During programming of the memory cell, the magnetic stack structure generates heat, and the gap delays heat loss.