Two kinds of CO2-responsive linear polymers， DTS-LP1 and BT-LP2， were reported. Both can change their hydrophilicity under CO2 regulation and thus can uniformly disperse in aqueous solution. At the same time， after the reaction， the polymer photocatalyst can be quickly separated and reused simply by removing CO2 from the system. In addition， the photocurrent and impedance were investigated by electrochemical measurements， where DTS-LP1 demonstrates a greater light current response intensity and small charge transfer impedance. The band position of these two polymers can be obtained by cyclic voltammetry （CV） characterization， indicating that it meets the oxidation condition of photocatalysis sulfides. When DTS-LP1 and BT-LP2 were employed as photocatalysts， the conversion rates of photocatalytic sulfide oxidation within 10 h were 97% and 42%， respectively， indicating that the polymer photocatalyst has excellent catalytic performance.