The paper presents the results of laboratory research concerning the evaluation of the quality of red-beet seeds sowing. Seeds of the Red Sphere red-beet variety were sowed using the operating unit of the S011 Alex seeder. A significant influence of the seeder operating speed on the sowing quality was observed, which was showed in percentages of red-beet single and double sowings and skips. The best precision of seeds distribution in a row was achieved at the S011 Alex seeder working speed of 0.7 m s-1 and the speed of its belt movement of 0.5 m s-1. Increase of the seeder operating speed above 0.7 m s-1 caused a deterioration of red-beet seeds distribution in a row. Thus, it can be concluded that the seeder operating speed significantly impacted the quality of sowing of red-beet of the examined variety in laboratory conditions.