The authors have adopted the algorithm of the correlated adjustment. According to this method, the redundant observation components of the observations and the norm of the internal reliability of all kinds of observations in the traverse network can be calculated. Based on the theory of statistics and hypothesis test, the statistical components, which are applied to inspect the gross error of the observations, have formed. By means of detection, the observations which may contain the gross error can be pointed out. In the end, the analysis of the internal reliability is put forward. At the same time, the paper gives suggestions on both the design of the traverse network and the point in measurements.