The paper is devoted to an experimental and theoretical study of effect of small angle of attack on disturbances evolution and laminar-turbulent transition in a supersonic boundary layer on swept wing. The experiments were conducted at the low nose supersonic wind tunnel T-325 of ITAM at Mach numbers M=2. Model is a symmetrical wing with a 45°sweep angle, a 3 percent-thick circular-arc airfoil. Calculations on the effect of small angles of attack on the development of perturbations are made in the framework of the linear theory of stability. Obtained good qualitative correspondence of experimental transition Reynolds number and the calculated dependences obtained for different values of the N factor. For the first time a comparison of the experimental growth rates with the results of calculations for various angles of attack was made. A good agreement between the experimental and theoretical data for the zero angle of attack was obtained. At the same time, there was no such agreement at non-zero angles of attack.