In this work we present a theoretical investigation of optical absorption in a spintronic superlattice. It is shown that the Rashba spin-orbit interaction can be used to control the characteristics of the absorption. Our results suggest possible experiments to detect such tunable absorption spectra. The underlying mechanism is the level splitting and linear energy dispersion, both are the consequences of spin-orbit interaction. The proposed absorption properties can be useful in developing spintronic devices in the terahertz regime.