Abstract：As comparing with the ITRF2000, the ITRF2005 make a lot of improvement on solution generation, datum definition and realization and so on, so there is a certain frame difference between the ITRF2000 and ITRF2005, furthermore, it would affect GNSS data processing. So in this work, the differences of the results including station coordinates, baseline length and horizontal velocity field were analyzed. After transformation, the differences of position are at millimeter level, the differences of baseline length are less than 1mm. The differences of horizontal velocity fields decreases with the reduction of studied area. For large regions, the differences are less than 1mm/a and a systematic difference of about 2 degrees in direction. For medium regions, the differences and direction are not significant.
