In this work,Raman scattering measurements have been performed on the collapsed phase CaCo_2As_2 crystals.At least 8 Raman modes were observed at room temperature though CaCo_2As_2 is structurally similar to other 122 compounds like BaFe_2As_2.Two Raman modes are assigned to the intrinsic A_(1g)and B_(1g)of this material system respectively.The other ones are considered to originate from the local vibrations relevant to cobalt vacancies.Careful polarized measurements allow us to clearly resolve the four-fold symmetry of the B_(1g)mode,which put strong constraints on possible point group symmetries of the system with Co vacancies.The temperature-dependent measurements demonstrate that the anomalies in both frequency and width of the B_(1g)mode occur around Neel temperature T_N.The anomalies are considered to be related to the gap opening near the magnetic transition.The study may shed light on the structural and magnetic changes and their correlations with superconductivity in 122 systems. Raman scattering measurements have been performed on the collapsed phase CaCo_2As_2 crystals. At least 8 Raman modes were observed at room temperature though CaCo_2As_2 is structurally similar to the other 122 compounds like BaFe_2As_2.Two Raman modes are assigned to the intrinsic A_ (1g ) and B_ (1g) of this material system respectively. the other ones are considered to originate from the local vibrations allow us to clearly resolve the four-fold symmetry of the B_ (1g) mode, which put strong constraints on possible point group symmetries of the system with Co vacancies. temperature-dependent measurements demonstrate that the anomalies in both frequency and width of the B_ (1g) mode occur around Neel temperature T_N.The anomalies are considered to be related to the gap opening near the magnetic transition. The study may shed light on the structural and magnetic changes and their correlations with superconductivity in 122 syste. ms.