The appearance and distribution of stresses in a steel plate with an aperture during its stretching in an elastic area has been studied experimentally. An IN-5101A automatic device, developed by INKOTES, was used during the experiments. The experimental results of stress determination using the acoustoelastic procedure have been compared with the results of analytical calculation. The experiments showed that the nondestructive ultrasonic method of investigation of stress concentration in the vicinity of apertures can be used widely.