Abstract: A phase change memory device and, more particularly, to a phase change memory cell array suitable for the implementation of a high-density memory device. The phase change memory cell array includes a first access transistor pair and a second access transistor pair formed on a semiconductor substrate to be adjacent to each other while each of the first and second access transistor pairs having a common drain, phase change resistance elements formed on source regions of the access transistors, respectively, and a semiconductor region formed on the same plane as the common drains to electrically connect the common drains of the first and second transistor pairs. The phase change memory cell array and the memory device of are suitable for the implementation of a high-density semiconductor device, and capable of improving the reliability of a contact forming process by securing a sufficient space for the contact forming process.