The achievement of high yields is the primary objective of modern agricultural production. Increasing the volume of the farm output is the focus of every farmer’s attention. Maise is a highly productive crop with a wide range of applications. The food, industrial, and agro-technical importance of maise point to the need for continuous improvement of cultivation technologies, increasing yields and grain quality under local climate conditions to obtain the highest economic efficiency. The conditions of Western Siberia are characterised by insufficient moisture supply during the growing season. States in Western Siberia are represented by a pronounced continental character with cold, long winters and short, hot summers. Thus, insufficient moisture is a limiting factor for the yield of most crops, including maise, especially in some critical periods. In the present study, the authors evaluated maise yield and structure with and without irrigation. A positive effect of irrigation on the elements of maise yield (length, width and circumference of the cob, number of grains in the row and on the rim, weight of 1000 grains) was noted. The authors also note a significant increase in hybrid Kubansky 101 and Katerina SV yield. The biochemical composition of grain: dry matter, sugars, fat, starch, protein and dextyrins content was studied. It was found that the amount of dry weight in grain on rainfed fields is higher than on irrigated fields, while all other indicators are higher with irrigation.