Abstract: The diluted magnetic semiconductors Cu_1-xCo_xInTe₂ (Co doping ratio x=0, 0.1, 0.2, 0.3) was synthesized through vacuum arc melting. X-ray diffractometer (XRD), vibrating sample magnetometer(VSM), and UV-Vis-NIR spectrometer were used to investigate their crystal structures and magnetic and optical properties, respectively. The main phases of Cu_1-xCo_xInTe₂ crystalline has tetragonal structure with a space group of I42d. The atomic occupations are 4a(0, 0, 0) for Co and Cu atoms, 4b(0, 0, 1/2) for In and 8d(x, 1/4, 1/8) for Te, respectively. Cu_1-xCo_xInTe₂ shows room temperature ferromagnetic characteristics, and their field dependence of magnetization follows a Langevin model. Their saturation magnetization increases with increased x. The bandgaps of Cu_1-xCo_xInTe₂ can be adjusted by controlling the doping amount of Co, which makes possible its potential application as photovoltaic material.