Abstract: Based on the PANDA software,the method of square root information filter (SRIF) is used by processing IGS stations real-time observation data and solving by model of single epoch. Broadcast the GPS clock information to the user. Hence,users can precise positioning in real-time. The results indicate that the differences of real-time precise clock from the IGS final precise clock products are better than 0.2 ns,which is the same accuracy level as those of all IGS analysis centers.