The best experimental factors were achieved through the single factor experiment and orthogonal experiment. When the initial concentration of formaldehyde was 120mg/L, reaction time was 30 minutes and the ratio between amount of sodium bisulfite and formaldehyde was 3:1, the removal rate of formaldehyde was approximately up to 100%, which fully satisfied the national emission standards (the concentration of formaldehyde≤ 1mg/L). The actual wastewater project was verified according to these factors. The tannery wastewater containing formaldehyde which the initial concentration of formaldehyde was 120mg /L was reacted with sodium bisulfite. The concentration of remaining formaldehyde was reduced to 0.446mg/L 30 minutes later, which fully satisfied the national emission standard. The process was practicable.