The present invention provides an acoustic attenuation based on sound ray deflection theory and a muffler. The method of the present invention provides a temperature gradient between the interior and the exterior of the chamber of the muffler through the low temperature refrigeration system, in which the temperature inside the pipe wall is higher than that outside the pipe wall. The said temperature gradient may deflect the acoustic ray towards the low temperature direction, so as to capture and reduce the noise. The muffler of the present invention comprises a muffler housing laid with a sound absorbing structure (4) on its internal surface, is characterized by the low temperature refrigerating system (2) which is fixed in the position corresponding to the sound absorbing structure (4) on the external surface of the muffler housing (1), covers at least 5% of the area of the external surface of muffler housing (1), and is used to realize quantitative control of the temperature gradient together with a temperature control system (3). The muffler of the present invention effectively improves the noise-absorbing effect of the prior muffler.