A portable keyboard includes: a polygonal pillar-shaped main body having a battery embedded therein; a key assembly connected to the main body, the key assembly having a plurality of key arrangements; and a connecting member formed to extend down to the bottom of the key assembly while connecting the key assembly and the main body to each other, wherein at least one key arrangement in the key assembly allows information to be entered by a touch, a first element is provided to the main body, a second element is provided to the key assembly, and the first element and the second element are attached to each other by magnetic force such that the key assembly is wound.