The invention provides a near-surface Q-value inversion and classified evaluation method based on generalized S transform. The near-surface Q-value inversion and classified evaluation method comprises the steps of: step 1, sorting data of two adjacent channels; step 2, respectively applying generalized S transform on the data of two adjacent channels to obtain high-resolution time spectra; step 3, extracting corresponding instantaneous amplitude spectra of first arrival signals; step 4, adopting a logarithmic spectrum ratio method to perform inversion fitting to obtain a Q value between two channels; step 5, repeating the steps from (1) to (4), and performing inversion to obtain Q values between adjacent channels in all micro-logging data; step 6, generating curves of the Q values varying with depths at the well positions; step 7, calculating an average attenuation effect factor by combining layer thicknesses and layer velocities; step 8, and performing near-surface classified evaluation by taking the average attenuation effect factor as a benchmark. The near-surface Q-value inversion and classified evaluation method based on generalized S transform studies the acquisition method for deeper complex structure and stratum lithology exploration, improves the acquisition quality and efficiency, and provides effective technical support and guarantee.