With the development of reservoir performance, the reservoir fluid distribution in Baobei changes accordingly, and the permeability of reservoir gradually reduced as well. The currently injector spacing of Ⅰ-Ⅱ oil group is 260 m, it is difficult to establish an effective driving system, it is unable to meet the needs of current injection. The water injection intensity of reservoir is too high, and part of the injectors doesn’t work. This paper applies methods such as, section pressure gradient method, empirical formula technology of reasonable well spacing, investigation radius method, and economic limit well spacing method, and based on comprehensive comparative analysis of the advantages and disadvantages of various methods, and then proposes the reasonable spacing aboutⅠ-Ⅱ oil group in Baobei region. The analysis concludes that, the current injection well spacing of Ⅰ-Ⅱ oil group is too far. To establish an effective drive system and improve the oil displacement efficiency of producer-injector well, the reasonable well spacing should be 170 m (distance of the well spacing is related to oil prices). Under the existing conditions, the well spacing should be adjusted in field.