Abstract The accuracy of horizontal velocity measured by GNSS mobile observation was evaluated by continuous observation, and the effects of difference of observation time period between two adjacent observations, observation time and observation cycle on the accuracy were also analyzed. The results show that, according to the current observation style, the absolute value of difference of horizontal velocity between mobile and continuous observation is less than 3mm/a. The difference of observation time period between two adjacent observations can affect the accuracy of horizontal velocity. If the difference which is less than 3 mm/a can be accepted, it is suggested that the difference of observation time period in the two years should be less than 25 days. The accuracy can be improved by prolonging observation period and shortening observation cycle.
