The K dwarf star XO-2 (GSC3413-5) has an exoplanet with an orbital period of 2.616 days and mass 0.57 Mjup. The host star XO-2 has a common proper companion with 31“separation and these stars are nearly identical. The distance of this object is about 486 ly. We observed XO-2b exoplanet transit first time at Taurus Hill Observatory Varkaus, at the 20th/21st of August. We detected that the beginning and the end of the transit was some minutes later than predicted but the transit time itself was as long as in prediction, 162 minutes. We used GSC3413-210 (C1) and GSC3413-13 (C2) as check stars. The exposure time was 40 sec with C-filter. The object was about 25 – 35 degrees above the horizon in the northeast sky. Temperature was 13 degrees and humidity 80 %. There was small fog and many light clouds in the sky at times through the observing period. That is why there is quite high deviation in the light curve. Observing team: Veli-Pekka Hentunen, Markku Nissinen and Veikko Kauhanen.