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An ultra-thin terahertz (THz) perfect metamaterial (MM) absorber with multi-spectral characteristics is reported in this paper. The MM absorber has a compact geometry and is developed on a polyimide substrate supported by a silicon wafer. The conductive regions of the perfect MM absorber are created using copper. The MM absorber has a square lattice and the unit cell is patterned using concentric L-stubs connected to a central stub along one end of the L-sections. These structures are rotated and distributed along the four sides to obtain a polarization-independent absorber unit cell. The proposed absorber has six distinct frequency bands between 0.45 and 2.2 THz. The absorptivity in each of the frequency bands is greater than 90% with a peak absorption of 99% at 1 THz and 1.56 THz. The absorber is tested for angular independence and the performance is found stable up to 60°. Furthermore, the absorber as …