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With emergence of the BeiDou Navigation Satellite System ( BDS) , the Galileo Satellite Naviga-tion System ( Galileo) , the Quasi-Zenith Satellite System ( QZSS) and the restoration of the Global Navigation Satellite System ( GLONASS ) , the single Global Positioning System ( GPS ) has been gradually expanded into multiple global and regional navigation satellite systems ( multi-GNSS/RNSS) .In view of differences in these 5 systems, a consolidated multi-GNSS/RNSS precise point positioning( PPP) observation model is deduced in this contribution.In addition, the performance evaluation of PPP for multi-GNSS/RNSS is conducted using a large number of the multi-GNSS exper-iment ( MGEX) station datasets.Experimental results show that multi-GNSS/RNSS can guarantee plenty of visible satellites effectively.Compared with single-system GPS, PDOP, HDOP, and VDOP values of the multi-GNSS/RNSS are improved by 46.8％, 46.5％and 46.3％, respectively.As for convergence time, the static and kinematic PPP of multi-GNSS/RNSS are superior to that of the sin-gle-system GPS, whose reliability, availability, and stability drop sharply with the increasing eleva-tion cutoff.At satellite elevation cutoff of 40 °, the single-system GPS fails to carry out continuous positioning because of the insufficient visible satellites, while the multi-GNSS/RNSS PPP can still get positioning solutions with relatively high accuracy, especially in the horizontal direction.