GPS 技术已经渗透到测绘学科的各个领域，同样在水准测量中也已得到广泛应用。 GPS 测高具有效率高，经济实用的特点，有着传统水准测量无可比拟的优势。而且GPS 水准高程拟合技术也已日臻完善，它的关键在于如何将没有物理意义的大地高转换成具 有使用价值的正常高。通常的做法是将高程异常作为研究对象，根据情况的不同，建立 合适的数学模型，结合重力模型用移去恢复法进行拟合。如今，GPS 水准高程拟合精度 一般可以达到厘米级，在很多情况下都可以满足实际生产的需要。 随着CQG2000 和省市级似大地水准面的建立，给GPS 测高方面带来了很大的便利， 但是其精度难以满足高精度的测绘工作，于是，在CQG2000 的基础上，各省市着力研 究各自的区域高精度似大地水准面，至今已取得不少成果，精度相对于CQG2000 已提 升了一个档次，但这些区域似大地水准面还有提升的空间。本文以此为研究背景，以江 苏省某市为研究对象，探讨了在已有似大地水准面的情况下进一步精化小区域似大地水 准面的方法和可行性。并开发一套相关的数据处理软件来进行数据解算和精度分析。 本文首先系统的介绍了精化似大地水准面相关的概念和各种精化似大地水准面的 方法，然后着重介绍了其中的GPS/水准拟合法。并分别用多项式拟合法、多面函数拟 合法、加权平均拟合法和最小二乘配置法试算和分析各自的适用范围，进行精度和实用 性比较。接着研究了在已有似大地水准面的基础上利用移去-恢复法和GPS/水准拟合法 进行区域似大地水准面精化的可行性，给出了具体思路和计算步骤，并利用实际数据对 此方法的可行性和优越性做了分析和探讨。最后以Visual Basic 为平台，通过无缝连接 Matlab 开发了相关的一套解算软件。

The technology of GPS has infiltrated into different fields of Geomatics,besides, it has been widely used in leveling surveying。It has a lot of advantages as follows: Compared with the traditional leveling surveying，it is high-efficient as well as practical. On top of this, the technology of GPS elevation fitting is becoming better and approaching perfect day by day,the key of which lies in how to switch the geodetic height without any physical significance to the valuable normal height.As a rule, according to different situations, we use height anomaly as the subject of study and set up proper mathematic model,then use Remove- Restore Technique to fitting with the gravity model.Nowadays, the accuracy of GPS elevation fitting can reach up to centimetre-sized, which can meet the needs in many circumstances. Although the establishment of CQG2000 and quasigeoid in the provincal and municipal agreements brings a lot of convenience to the elevation with the use of GPS, the accuracy of those above can’t satisfy the requirement of Geomatics .Thus, based on the CQG2000,many provincal and municipal organizations has made efforts to study precise Quasi-geoid in their own district,making great achievements so far.Among these,compared with CQG2000, the accuracy has improved into a new level,but we still need further study in the potential of local Quasi-geoid. Taking this background into account, in this paper,I will use certain municipality as the subject of study and analyze the approaches and possibilities of précising local Quasigeoid which is based on Quasi-geoid,what’s more, I will devise a set of software dealing with some data in order to the calculation and the analysis of accuracy. In the first place, I introduce the concept of Quasi-geoid and something related as well as the way to accurate Quasi-geoid. Then, GPS/Leveling, which is one of the ways of accurate Quasi-geoid, comes second. In this part, after using polynomial fitting 、Multisurface Function、weighted average method、andLeast Squares Collocation to calculate and analyze their range of use respectively, I compare their accuracy and practice . Next, based on the existing of Quasi-geoid,some research are made on the probability that whether we can use Remove-Restore Technique 和GPS/Leveling to accurate local Quasi-geoid or not. In this research, I present the concrete thoughts and steps to calculation and use some real data to analyze as well as probe into the probablity and advantages of this method. The last but not least, with Visual Basic being a platform, I design a set of software to comput the date with the link of matlab。