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Earth rotation parameters (ERPs) are necessary parameters to achieve mutual transformation of the celestial reference frame and earth‐fix reference frame.They are very important for satellite precise orbit determination (POD),high‐precision space navigation and positioning.In this paper,the determination of ERPs including polar motion (PM),polar motion rate (PMR) and length of day (LOD) are presented using BDS and GPS data ofJune 2013 from MEGX(Multi‐GNSS Experiment) network based on least square (LS) estimation with constraint condition.BDS and GPS data of 16 stations from MGEXnetwork are the first time used to estimate the ERPs.The results show that the RMSs of x and y component errors of PM and PM rate are about 0.92 mas,1.0 mas,0.20mas/d and 0.32mas/d respectively using BDS data.The RMS of LOD is about 0.028ms/d using BDS data.The RMSs of x and y component errors of PM and PM rate are about0.19mas,0.21mas,0.18mas/drespectively using GPS data.The RMS of LOD is about 0.021ms/d using BDS data.The optimal relative weight is between 1:2 and 1:3.The accuracy improvements of BDS is about 14% in X component of PM,8% in Y component of PM,21% in X component of PM rate and 17% in Y component of PM rate.There is no obvious improvement in LOD when BDS data is involved.System biases between BDS and GPS are resolved and they are different with different station and very stable day to day with about 20 cm accuracy.