PURPOSE: To carryout simple and quick roasting of coffee beans in general households using a sealed storage container by putting colored marking coffee beans into a container made of aluminum foil, with a transparent film cover followed by closing said container and by roasting while rocking.

CONSTITUTION: A simple roaster A, i,e., a dishlike container a made of aluminum foil fitted with a cover b made of transparent and moisture-proof cellophane and a grip c is charged with raw beans or semi-roasted coffee beans B, and furthermore, spiked with colored marking coffee beans B'. The resultant system is then put on a gas cooker and roasted while rocking, and when popping sound is heared, the stopper piece 13 of the cover b is cut off by pulling a projection 14 to open a vent 3 to release smoke, etc., into the air. The roasting is continued until the color of the beans A changes into that desired while monitoring the beans B, thus obtaining the objective coffee beans.