Abstract: With the development of marine surveying techniques,in order to obtain the position parameters as accurate as possible more attention should be paid to the data-processing.For example,in the practice of positioning for marine geophysics exploration,it is often difficult to estimate the position using coventional method because of the existence of gross error in the measurements.At present,there is little work done concerning outliers in marine surveying.This paper tries to solve the following problems:1) How to discover the outliers in measurements and to obtain accurate position parameters.2) Put forward some suggestions on the field work.