In order to better understand how green manure retain and supply water through enhancing soil physical structure，this study investigated the effects of different fallow managements over years on soil compactness，soil water storage potential，and soil pore distribution of a typical fluvo-aquic soil. The experiment was conducted at a long-term experimental field at Xinxiang Irrigation Institute，Chinese Academy of Agricultural Sciences，Xinxiang city，Henan province，China. Five fallow management treatments were set up:winter wheat(WW)，winter fallow(WF)，Vicia villosa Roth.(VR)，Brassica napus L.(BN)，and mixed Vicia villosa Roth-Brassica napus L.(VR-BN). Soil bulk density，soil penetration resistance，water-storage potential，and soil pore distribution(the percentages of storage pores，capillary pores，and aeration pores)of these five fallow management treatments were analyzed. The results showed that green manure treatments reduced soil bulk density at the 10-20 cm depth from 1.65 g/cm3 in winter wheat to 1.48，1.52 and 1.51 g/cm3 in VR，BN and VR-BN treatments，respectively. The VR and BN treatments also significantly reduced soil bulk density at the 20-40 cm depth. The VR，BN and VR-BN treatments were able to decrease soil penetration resistance at 20-30 cm depth compared to the WW treatment，where the plow layer in the WW treatment had a maximum penetration resistance of 557 kPa. In the plow layer，the penetration resistance of the VR-BN treatment was 14.90% lower than the WW treatment，alleviating soil compaction. The soil water storage potential at 0-40 cm was significant higher in the VR，BN and VR-BN treatments than that of the WW treatment. In detail，the VR treatment mainly increased the soil water storage potential at the depth of 10-20 cm，while the VR-BN treatment mainly increased the soil water storage potential at the depth of 10-30 cm. Fallow treatments primarily changed the soil pore distribution at the 0-30 cm depth:at 0-10 cm soil depth，the VR-BN treatment enhanced the percentage of storage pores；at 10-20 cm soil depth，the VR-BN treatment increased the capillary pores by 28.96%，and both VR and BN treatments increased the percentage of aeration pores；at 20-30 cm soil depth，the VR-BN treatment significantly increased the percentage of capillary pores by 32.78%. Long-term fallow managements of villose vetch and winter oilseed rape could significantly alleviate soil compaction at the plow layer depth. The incorporation of villose vetch biomass into soil could reduce the soil bulk density and increase soil water storage potential. The mixed sowing of villose vetch and winter oilseed rape could improve the proportion of subsoil capillary pores and surface storage pores. By optimizing the soil pore distribution，the mixed sowing of villose vetch and winter oilseed rape enhanced the soil profile’s water storage，hence facilitating more efficient water uptake in the subsequent summer maize season. Growing of green manure such as villose vetch and winter oilseed rape could be an approach of achieving water-saving agriculture in the Huang-Huai-Hai region.