Disclosed is a microspeaker with an inner resonance chamber, more particularly a microspeaker with an inner resonance chamber which improves quality of sound and enables slim and compact design of the microspeaker by blocking rearward sound generated at the rear side of the vibration plate to prevent interference of a rearward sound with a forward sound generated at the front side of a vibration plate and installing a chamber with a specific volume within the microspeaker to allow the rearward sound to cause resonance.