A key for keyboard-based musical instrument is provided for ensuring high hydrophilia and thereby ensuring higher playing performance. A key 1 for an electronic piano 2 comprises a key body 10 made of an ABS resin, and a thin plate-shaped key touch member 11 adhered on the top surface of the key body 10. The key touch member 11 comprises a base 11b made of an ABS resin, and a hydrophilic polymer 11a added in the base 11b in a dispersed manner. While a player is playing a keyboard-based musical instrument, sweat at the tip of his/her finger is absorbed by the hydrophilic polymer 11a.