B-values are the difference of pseudorange corrections for multiple reference receivers on GBAS (Ground Based Augmentation System). It is one of important parameters for the ground system integrity monitoring, which is used as a basic reference for the integrity risk estimation based on reference receivers’ failure. For single satellite navigation system, the residual of pseudorange corrections is adopted in the B-value processing. However, an independent analysis and integrated processing are necessary for detecting the failure of multiple reference receivers. Therefore, a new B-value algorithm available for multiple systems is put forward based on the traditional B-value processing method and the analysis of GPS data. The algorithm can be used for integrity monitoring for future GNSS GBAS system.