Аннотация:We present the results of our long-term (13 years) J and K photometry of the X-ray binary Cyg X-1. The object's JK variability amplitudes were less than 0 2. The J and K orbital light curves are appreciably asymmetric in quadratures. The secondary minimum is deeper, in comparison to the primary, and it is probable that the star becomes hotter at secondary minima. The ratio of average radii of the supergiant in quadratures and in minima is 1.02 if the temperature of the optical component does not change during its orbital motion. We estimate the interstellar extinction as and the distance to the star, as kpc. The luminosity and radius of the optical component are respectively and . The JK variations of the X-ray binary Cyg X-1 in 1995-2007 can be explained with orbital ellipsoidal variations of the optical component (hot supergiant HD 226868), accompanied with long-term JK variations on a time scale of 11.5 years with an amplitude of 006-007. In 1995-2007, the JK brightness fluctuations probably had a 294-day periodicity with an amplitude of no more than 003-005.