PURPOSE: A sound producing device for cup attachment is provided to output effective sound which is suitable for situation by sensing the luminance of the cup. CONSTITUTION: A context recognition unit(11) senses the luminance inside of a cup. The context recognition unit recognizes the state of the cup. A sound storage unit(12) outputs the sound data which is suitable for a context signal of the situation recognition unit. An audio amplifier(13) changes the sound data of the sound storage unit into an audio signal. A piezoelectric speaker(14) reproduces the input signal of the audio amplifier.
