The one-hour UT1 (Universal Time) intensive observations carried out by VGOS (VLBI ((Very Long Baseline Interferometry)) Global Observing System) single baseline in 2021 are analyzed. It shows that the RMS (Root Mean Square) of the difference between UT1 measured by VGOS and UT1 provided by IERS (International Earth Rotation Service) C04 is 25.3μs, which is better than 28.2μs of traditional S/X UT1 intensive observation (INT1), and the mean formal error of UT1 is improved from 14μs to 7μs. Because the scan number of VGOS observations is twice that of INT1 in one hour, the measured UT1 is more stable under the impact of errors in polar motion. 100μas errors in polar motion will introduce a 2.8μs offset in UT1. In addition, the data of VGOS half-hour observation is analyzed. The UT1 result is equivalent to the one-hour, indicating that the VGOS half-hour observation can be used for the ultra fast service of UT1. At the same time, this paper analyzes and evaluates one-hour UT1 intensive observation on Sheshan 13m and Nanshan 13m baselines. The RMS of eight observations is 46.2μs and the average formal error is 17.7μs, which is significantly improved compared with the Sheshan 25 m and Nanshan 25m baselines.