A new soft optoelectronic function material, which can transmit optical and electrical signal simultaneously, was made by injecting ionic liquids (ILs) into a quartz capillary tube with the inner diameter of 0.32 mm. 10 types ILs were used to make transmission media and their characteristics were studied experimentally. It is found that optical and electrical signal can transmit respectively when the frequency of electric signal is higher than 10 Hz. The numerical aperture of the medium can achieves 0.554, which is bigger than that of the traditional optical fiber transmission medium. The attenuation is relative to both the types of ILs and wavelengths. The impedances are sensitive to temperature, and at the same temperature the impedance disparity of different transmission media can reach more than 10 times. The maximal AC voltage that the medium can transmit increases with the increase of frequency.