The invention relates to the field of mufflers, and particularly provides a three-layer series micro-perforated pipe muffler which comprises a muffler body, an intake end and an exhaust end. The muffler body is of a three-layer micro-perforated pipe structure for muffling, aperture ranges from 0.1mm to 0.5mm, porosity is less than 5%, gaps are formed between three-layer micro-perforated pipes without being filled with filling materials, the three-layer micro-perforated pipes are different in aperture, equal in porosity and different in cavity volume, and noise in different frequency bands is eliminated. When the muffler is at work, airflow directly flows through a pipeline, and back pressure loss is low. The exhaust muffler is simple in structure, convenient to process and low in cost, and is resistant to high temperature, corrosion and airflow impact and long in service life as being of a pure-metal structure. The muffler has good muffling effect in the whole spectral range and particularly in high-frequency band, and muffling volume reaches 15-25dB.