Low-power plasma-sprayed Cr/Al2O3 coatings have been developed for their potential application as broad bandwidth, thin thickness, lightweight, and strong microwave-absorbing materials. The dielectric and microwave absorption properties of the as-sprayed coatings were studied in the X-band (from 8.2 to 12.4GHz). High complex permittivity of the coatings was obtained because of a large number of internal boundaries and the conductive networks. Meanwhile, a significant enhancement of microwave absorption properties of the coating was achieved due to the enhanced interfacial polarization and conductance loss. The reflection loss (RL) <-10dB of the Al2O3-15Cr coating was obtained from 9.8 to 11.4GHz by choosing an appropriate coating thickness, and an optimal minimum reflection loss (RLmin) of -45.35dB was achieved at 10.3GHz with a thin thickness of 1.32mm.