The paper presents experimental results concerning cultivation of different mustard types under conditions of the Southern Steppe of Ukraine and the effect of growing techniques on the indexes of seed quality. The research made it possible to establish that using the seeds of the 4th generation for sowing, in comparison to the elite seeds, causes a decrease in the level of the seed productivity by 50.5% and that of oil content – by 12.5%, winter-hardiness of winter Sarepta mustard falls by 59.5%. In order to obtain filled seeds it is necessary to sow mustard seeds with a traditional row method with the row spacing of 15 cm. To obtain high-quality seeds it is necessary to apply one-stage combine harvesting with further obligatory primary seed cleaning to remove impurities, not later than 4 hours after harvesting. Optimum basis moisture of mustard seeds is 8%. Basis moisture can be raised to 12% for the seeds of winter Sarepta mustard, whose shelf life does not exceed 60 days, moisture should be decreased to 8%, in case of creating backup funds of the crop. The shelf life that allows the seeds of white and black Sarepta mustard to retain their seeding standards is three years provided that they are stored in stacks of not more than five sacks