The variance of centroid displacements has been experimentally measured for a laser beam intersecting a turbo-engine jet at different angles (j = 90, 45, 10°). The obtained values range from 60 to 180 mrad for l = 1.06 mkm and from 110 to 300 mrad for l = 0.53 mkm. A difference has been found between the variances of beam wandering in the horizontal and vertical (orthogonally to the jet axis) directions. An analytical model developed for calculating the variance of laser beam wandering agrees with experimental data. The experimental results have allowed us to assess the high-frequency component of refraction index fluctuations in the jet, which supplements the von Karman spectrum for a turbulent medium.