A key top member for a push button switch structure capable of facilitating change and modification of a design while eliminating deformation and misregistration of a display section, being accommodated to a variety of data, being increased in design properties and visibility, and being reduced in manufacturing cost. An upper resin sheet made of thermoplastic resin and having display sections such as a letter, a symbol, a pattern or the like printed thereon is formed with projections having configurations conforming to outer configurations of key top elements. The projections are each securely provided therein with a filler member made of photo-setting resin directly or through an adhesive.