Аннотация:MASTER-Tavrida robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Lomonosov MSU, SAI Crimea astronomical station) was pointed to the Swift GRB210422.74 (trigger No 1044678,01h 24m 33.36s , +42d 06m 36.0s, R=0.05) errorbox 39 sec after notice time and 23084 sec after trigger time at 2021-04-23 00:11:54 UT, with upper limit up to 16.3 mag. The observations began at zenith distance = 84 deg. The sun altitude is -24.0 deg. The galactic latitude b = -20 deg., longitude l = 130 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=1599524 We obtain a following upper limits. Tmid-T0 | Site |Filt.| Expt. | Limit| Comment _________|_______________ ______|_____|_______|______|______ __ 23175 | MASTER-Tavrida | C | 180 | 16.2 | 23374 | MASTER- Tavrida | C | 180 | 16.3 | Filter C is a clear (unfiltred) band. The observation and reduction will continue. The message may be cited.