The present invention discloses a diaphragm and a miniature speaker comprising the diaphragm. The diaphragm has a multi-layer composite structure comprising alternately stacked thermoplastic elastomer layers and adhesive film layer(s). The diaphragm and the miniature speaker comprising the same solve the technical problems such as an unstable F0 and high total harmonic distortion of the miniature speaker in the prior art. The diaphragm and the miniature speaker according to the invention have low total harmonic distortion, low damping coefficient, higher F0 stability and high sound quality, satisfying requirements for high sound quality of an electronic device.