The work aims to optimize the electrochemical preparation process of ZnO and improve the photocatalytic performance of thin films by silver modification. Single-factor experiments were used to evaluate the activity and stability of the films. The photocatalytic activity and stability of electrochemically and photocatalytically deposited silver ZnO films were studied. The effects of hole-agents, photocatalytic time and concentration of silver nitrate on zinc oxide films were studied. The films were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). When the current density was 3.33 mA/cm2 and electrolysis time was 10 min, the decolorization rate of the prepared pure zinc oxide film gold orange II was the best, and the decolorization time was positively correlated with the decolorization rate. Electrochemically deposited silver film had serious shedding phenomenon with larger error. With the addition of 0.05 mol/mL silver nitrate, zinc oxide film with photocatalysis for 10 min had better stability and removal rate and the smallest decolorization rate. The film did not exfoliate and the decolorization rate was low when 0.05 mol/mL ethanol was added in the selected hole scavenger. Zinc oxide film of the photocatalytic deposition silver contained zinc oxide at 2θ=30.92° and 26.3°; and contains the strongest peak of Ag at 2θ=37.9°. The films are the best when prepared at current density of 20 mA, electrolysis time of 10 min, concentration of zinc nitrate of 0.5 mol/mL, concentration of silver nitrate of 0.05 mol/mL, hole scavenger ethanol concentration of 0.05 mol/mL and photocatalytic time of 10 min. The silver-modified zinc oxide film is obviously better than the pure zinc oxide film in photocatalytic effect. Adding hole scavenger in the preparation of the silver-modified zinc oxide film has a better photocatalytic effect than the preparation without hole scavenger.