To make the dial button and other buttons of a portable telephone set easy to press with the tip of finger, to prevent the button from being erroneously pressed at the same time and to prevent unintended operation from unexpected pressing for starting each of functions when carrying the portable telephone set while putting it in an satchel or bag.

Push surfaces 13 of respective dial buttons 6 projected on the front of a machine body 1 for portable telephone set are made locally high and convex parts 13 are formed for forming projecting push parts.