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The residual of plastic film in soil continuously increased with the large application of agricultural plastic film during the last few decades. It destroyed the soil structure and seriously influenced the migration of soil water movement and solute. Saturated hydraulic conductivity and soil water characteristic curve are very important parameters for evaluating infiltration properties and simulating soil water and solute. Five residual film treatments (0, 5,100,200,400kg/hm2) were conducted to study the effects of different amounts of residual film on soil water infiltration and soil water retention ability and also to analyze the influences of residual film on soil structure based on CT images. The results showed that saturated hydraulic conductivity was significantly exponentially decreased with increase of residual film (p<0.05). When residual film reached 200kg/hm2, the saturated hydraulic conductivity reduced to 12% of non-residual film treatment. However, the soil was easily dehydrated and water retention ability was lowered with increase of residual film under high suction condition (>100kPa). There were good relationships between suction and soil water based on either van Genuchten model or Gardner model, and the parameters showed regular variation with the increase of residual film. The threshold CT images showed that black spot area clearly increased with the increase of residual film, and there was proportional relation between black spot area and residual film amount. The black spot areas were 19 times than non-residual film treatment, and the residual film significantly increased in soil.