The embodiment of the invention provides a method and a device for compensating absorption and attenuation of a stratum. The method comprises the following steps of: obtaining a seismic signal subjected to phase compensation at a pre-set position of a target stratum and a stratum quality factor of the target stratum; determining an amplitude-compensated gain control coefficient according to a pre-set gain control threshold value; constructing an amplitude-compensated shaping matrix according to a pre-set finite difference matrix and the gain control coefficient; obtaining an amplitude compensation action matrix of the seismic signal according to the shaping matrix, the stratum quality factor and the gain control coefficient; and carrying out amplitude compensation on the seismic signal according to the amplitude compensation action matrix and obtaining an amplitude-compensated result of the seismic signal. According to the method and device provided by the embodiment of the invention, the amplification factor of the amplitude compensation of a noise section of the seismic signal can be limited, so that the signal-noise-ratio of seismic information is guaranteed when the resolution ratio is improved.