In Uralsk Research Institute of Agriculture in 2007-2017 on dark gray forest soil impact of predecessors, the systems of fertilizers and weather conditions on the productivity of spring barley in crop rotations was stud-ied. The researches were conducted in 5 field crop rota-tions on three backgrounds of nutrition: control (without fertilizers), mineral and organic and mineral. From all years of supervision droughty conditions were noted in 2010, 2012, 2016, superfluous damp - in 2014-2015, in other years - moderate humidified conditions. For Cen-tral Ural Mountains the air drought when excess of av-erage daily temperature over norm during summer peri-od makes 2.3-4.1 °С, and the shortage of rainfall - only 6-21 % is more characteristic. It is moderated - humidi-fied conditions from all predecessors the greatest exit of grain of barley provided peas, under other conditions of moistening -winter rye, bare fallow. At moderate mois-ture security of vegetative period (hydrothermal coeffi-cient - 1.48) the maximum collecting grain on fertilized backgrounds of food is received on a clover within 4.33-4.41 t/hectare, on other predecessors - 0.11- 0.57 t/hectare lower. On average for 2 rotation the greatest productivity of barley at the level of 3.67-3.75 t/hectare is reached in grain grass and crop rotation (bean herbs of 20 %), the smallest exit of grain is re-ceived at its placement in grain-fallow-siderate (2 fields of clover) crop rotations. Return grass from 1 kg of of century of fertilizers on mineral background of food made 10.1-16.5 kg, at combined use of mineral and organic fertilizers payback from them decreased by 3.7-7.6 kg of grain.