Abstract:In order to analyze the accuracy of the earth rotation parameters solved by VLBI observation data, according to VLBI theory and error equation, we calculate the parameters using the VLBI data in 2020 and the XA and XB frequency channel data from continuous intensive CONT17 observation. We use the EOP14 C04 sequence as reference to obtain the external coincidence accuracy. The results show that the external coincidence accuracy of each component of rotation parameters can meet the requirements of high accuracy through the VLBI data. Compared with the continuous GPS data which are in the same period, the VLBI data present similar accuracy in calculating earth rotation parameters. The XA and XB frequency channel data perform similar accuracy in dealing with polar motion series, but the former performs better in stability and has great advantages in UT1-UTC sequence.