Electrical and optical properties of HgCdTe are crucial for detectors. Infrared photoluminescence (PL) spectra in the temperature range of 11-300K and Hall data were recorded on the arsenic-doped narrow-gap HgCdTe epilayers. Curve fittings of PL spectra indicate that AsTe、 VHg、 TeHg-VHg and TeHg exist in the arsenic-doped HgCdTe epilayers after the two-step annealing. More TeHg-VHg pairs are created when the dopant concentration is increased. Analysis of temperature-dependent Hall data verifies the existence of TeHg, which lowers the mobility of the material.