Objective Targeting at the current problems of fountain solution discharge， the technology and equipment of fountain solution loop filtration were developed, in order to achieve production cost savings, high efficiency and product quality improvement. Methods The method of two-stage filtering was adopted to treat fountain solution to promote recycling. The values of pH, conductivity and surface tension of processed fountain solution were tested for analysis. The untreated fountain solution and treated fountain solution were compared to study the filtering effect of filters with different aperture and the influences on the components of fountain solution and the quality of the products. Results The results showed that the pH and conductivity of fountain solution treated by 0.5 μ m PP cotton filter element were 5.27 and 720 μ s/ cm, and those treated by 1 μ m PP cotton filter element were 5.20 and 773 μ s/cm. The surface tension of fountain solution treated by the 0.5 μ m PP cotton filter element and the 1.0 μ m PP cotton filter element was 58.45 mN/m and 58.42 mN/m, respectively. The processed fountain solution met the requirements of normal printing. Conclusion Taking full consideration of all kinds of factors including cost and treatment effects, the combination of four 0.5 μ m PP cotton filter elements and four 1 μ m PP cotton filter elements was the optimal selection.