Abstract：The ununiqueness of estimated parameter is one of the problems in geodetic and geophysical inversion. Getting a best parameter is the research hot and difficulty in inversion problem. Prior information is very important to get the best parameter. The conventional method using the prior information is analysed. The inequality constrained geodetic inversion theory is given to solve the ununiqueness problem with the prior information.The advantages, key point and difficulty of this theory are discussed. The realization and classification method for this theory are given. Through an example this theory is analized.
