Multi-layer heterogeneous reservoir is commonly of interlayer interference，and therefore leading to low producing degree，low sweep efficiency and low recovery of waterflooding.The vertical heterogeneity seriously affects efficient development of low permeability reservoirs.The waterflooding experiment of single core and core combined model are carried out in this paper.The average permeability to water of core combined model is similar，so the influence of permeability ratio to the law of the waterflooding sweep is studied as well.The results show that the measured water absorption of core combined model corresponds to the theoretical formula of multi-layer heterogeneous reservoir.The displacement experiment of core combined model can accurately reflect the rule of the waterflooding sweep.As the permeability ratio is larger，the percentage of water absorption in high permeability gradually increases.When the permeability ratio is larger than 9，the injected water can hardly sweep the low permeability layer.