Аннотация:We performed our UBV observations of two program stars, V340 Ser and V448 Lac, at the Crimean Station of the Sternberg Astronomical Institute using a 60-cm Zeiss reflector with a photoelectric photometer designed by Lyuty (1971, Soobshch. GAISh 172, 30) with a 27 aperture. The accuracy of the observations was from 0.01mag to 0.02mag. The photometric system of the photometer is close to Johnson's standard UBV system.