Due to the sedimentary environment, diagenesis and tectonization, the thickness of sandstone distribution show heterogeneity, which affect the result of waterflooding efficiency. The single-phase flow mathematic model was built to reveal the characteristic of plane heterogeneous reservoir. The result which was obtained by discrete differential method demonstrated that outlet flow velocity during thin-thickness location injection and thick production is higher than thin-thickness location production and thick injection. Then numerical simulation was applied to analyse the rate of production and injection, recovery percent and reservoir pressure in reservoir units. The result showed that the reservoir pressure around injection well is lower and the production and injection rate is higher during thin-thickness location injection and thick production, which provide theoretical basis for the development of thick production and thin injection.