In the development of low permeability reservoirs, well patterns are placed along favorable orientation. There is such a possibility that fracture orientation will deflect due to reservoir heterogeneity and the fracture is likely to be on the unfavorable orientation,which may bring great risk to the development of oil field if it is improperly designed. In view of this problem, the suitability between well pattern and hydraulic fracture system in low permeability reservoirs is researched. Based on streamline simulation technology, the characteristic of liquid percolation of rhombus inverted nine-spot fracturing well pattern is analyzed. A numerical simulation model of integral fracturing with deflected fracture is established, taking X block as an example. The influence of different fracture parameters on production performance is studied. Results show that when the fracture orientation deflects, the characteristic of percolation field of fracturing well pattern altered obviously, thus the well symmetry element should be reformed according to the distribution of flow streamlines. The influence of fracture of different wells on production performance is distinct. Besides, there exists notable interference between two fractured wells. Increasing the fracture length of wells placed along unfavorable orientation has a little effect on enhancing oil recovery, and therefore it should be limited to a low value. Increasing the fracture length of wells placed along favorable orientation within a certain range has a great effect on enhancing oil recovery, and therefore it should be extended to a relative high value.