Abstract: The formulas of the pseudorange correction error are deduced. The existing integrity monitor method of the pseudorange correction error with excluding B value is analyzed, and some conclusions are obtained: the B values are correlative, if one B value is error, the other B values will be affected; the receiver error and the satellite error are not divided in the existing method, so the larger probability of fault detection and miss detection will occur. Two new methods are proposed to monitor the pseudorange correction error, which are named row and column estimation and assisting by C value. Analysis about the three methods is made by simulating six cases including no fault and five kinds faults, the results show that the two new methods probability of fault detection, miss detection, fault exclusion, miss exclusion are all smaller than the existing methods. Moreover, the position accuracy and continuity are improved. The two new methods are compared, and their advantage and disadvantage are discussed. Some suggestions are proposed on choosing methods.