An apparatus and method for tuning the volume of a sound downloaded from an outside source in a device for outputting such a sound through a speaker are provided. The apparatus includes a memory, a speaker, a microphone, a codec, a volume tuning determining unit, and a volume tuner. The memory stores a sound signal downloaded from the outside source. The speaker outputs the sound signal stored in the memory. The microphone receives the sound signal output from the speaker. The codec outputs modulation data of the sound signal input from the microphone. The volume tuning determining unit calculates volume figure data with respect to the sound signal, stress figure data of the speaker, and volume adjustment gain data using the modulation data. The volume tuner tunes the volume of the sound signal using the calculated volume adjustment gain data.