The invention relates to a method and device for preparing two-component sound-absorbing cotton through electrostatic spinning-dry laying. The method comprises the following steps that 1, 20-80 partsby weight of electrospun nanofibers and 20-100 parts by weight of dry fibers are composited to obtain an electrostatic spinning-dry laying two-component fiber net; 2, after the electrostatic spinning-dry laying two-component fiber net is utilized for cross laying till reaching the needed grams per square meter, post processing is conducted, and a finished sound-absorbing product is obtained. Accordingly, the two-component sound-absorbing cotton is prepared by compositing the electrospun nanofibers and the dry fibers; by means of the electrospun nanofibers of a nanostructure, the bore diameteris smaller, the porosity is larger, fibers close to the nanoscale can generate resonance with sound waves to attenuate energy, sound absorption is facilitated, more stagnant air is contained in sound-absorbing holes, and the thermal insulation property is better.