Magnetic memory devices include a magnetoresistive cell including a free layer having a variable magnetization direction and a pinned layer having a fixed magnetization direction, a bit line on the magnetoresistive cell and including a spin Hall effect material layer exhibiting a spin Hall effect and contacting the free layer; and a lower electrode under the magnetoresistive cell. A voltage is applied between the bit line and the lower electrode so that current passes through the magnetoresistive cell.