为提高单井产量以及研究特低渗透油田注水开发的控制因素，实现油田稳产高产。通过动态数据，试油、试采等数据进行整理分析，利用正方形反九点法对横山油田麻地沟区长4 + 5₂油层亚组井网进行注水见效分析，并对其影响因素进行分析。结果表明，油井见效分为明显见效、中等见效、微弱见效3种类型，分别占比为48.28%、41.38%、10.34%，见效方向主要以多向受效为主，其中在多向见效中又以五向见效为主。控制因素中主要有沉积微相、渗透率、井距3种，分流河道砂体发育，砂体越厚、连通性越好，油井越容易受效；油井注采见效程度好的，其渗透率也较好，渗透率越高，油井越容易受效；注采井距分布在150 ~ 300 m，说明井距并不是影响注采见效的唯一因素，而且井距大小的选择与研究区砂体厚度、连通性及储层物性密切相关。

In order to increase the output of single well and study the controlling factors of waterflooding in ultra-low permeability oilfields, the stable and high production of oilfields can be realized. Based on the collation and analysis of dynamic data, production test and production test data, the square inverse nine-point method was used to analyze the water injection effect and its controlling factors in the subgroup well pattern of Chang 4 + 5₂ reservoir in Madigou oil area of Hengshan oilfield. The results show that the effective effect of oil well can be divided into three types: obvious effective, medium effective and weak effective, accounting for 48.28%, 41.38% and 10.34% respectively. The main controlling factors are sedimentary microfacies, permeability and well spacing. Distributary channel sand body is developed. The thicker the sand body is and the better the connectivity is, the easier the oil well is. The better the injection-production effectiveness of the oil well is, the better the permeability is, and the higher the permeability is, the easier it is for the oil well to be effective. Injection-production well spacing is distributed from 150 m to 300 m, indicating that well spacing is not the only factor affecting injection-production effectiveness, and the selection of well spacing is closely related to sand body thickness, connectivity and reservoir physical properties in the study area.