Аннотация:The absolute visual and infrared magnitudes of moderately evolved OB-type stars are directly calibrated as a function of Stroemgren four-color and Hβ photometric indices using the trigonometric parallaxes from the new reduction of Hipparcos data. The resulting calibrations have an average accuracy of ~ 0.4 mag and, when applied to members of young open clusters, yield distances that are fairly consistent with those determined using the MV -(B - V) zero-age main-sequence fitting procedure.