The addition of liquid disperser in the packed bed supposing a biofilter was proposed to reduce the liquid channeling flow. Particles with different diameters and wettabilities were used as the immobilizing particle and the liquid disperser. The two-dimensional distribution of the liquid flow rate was measured by using a liquid collector consisting of 144 cups. The effect of addition of liquid disperser was evaluated by means of the standard deviation of the liquid flow distribution. The liquid channeling flow was much suppressed in the bed added with the liquid disperser than in the bed packed only with immobilizing particles. It is found that the hydrophobic liquid disperser is more suitable for the uniform distribution of the liquid flow.