Cr-doped CdGeAs2 polycrystal was synthesized by a single-temperature region combined with mechanical and temperature oscillation method, and Cr-doped CdGeAs2 single crystal with Phi 17 mm x 30 mm was grown by the improved Bridgman method. The crystal structure, electrical properties and doping content of Cr-doped CdGeAs2 were characterized by high-resolution XRD, Hall-effect and ICP, respectively. In the XPS measurement, the high-resolution scanning spectra of the Cr-doped CdGeAs2 crystals were obtained for the first time, and the binding energies of Cr 2p(3/2) are 575.44 eV and 576.50 eV, and the binding energies of Cr2p(1/2) are 583.06 eV and 585.14 eV by peak separation and fitting. Finally, FTIR was used to characterize the infrared properties of Cd-doped CdGeAs2 crystals. The results show that the transmittance near 5.5 mu m increases with a small amount of doping compared to undoped crystal, and reaches a maximum 42% when the Cr content is 0.057%. When the Cr content increases to 0.158%, the transmittance decreases slightly, and while the content reaches 0.324%, the transmittance of the whole wavelengths decreases sharply. Appropriate amount of Cr can reduce the absorption of CdGeAs2 near 5.5 mu m, improve its infrared transmittance and broaden its applications. (C) 2017 Elsevier B.V. All rights reserved.