The goal of the work was to determine which development stages of spring triticale are exposed to the most frequent occurrence of atmospheric drought and also to examine the quantity of reduction in grain yield depending on intensity of drought and a period of its occurrence. Periods of drought were identified through the relative precipitation index (RPI) and the hydrothermal coeffi cient K. The research used data from 34 experimental stations of the Research Centre for Cultivar Testing (COBORU), situated in whole Poland, encompassing the dates of sowing, emergence, tillering, shooting, heading, wax maturity and harvesting, and spring triticale grain yield in the years 1984–2004 as well as meteorological data, average air temperature and atmospheric precipitation total, from stations of the Institute of Meteorology and Water Management (IMGW) located in the vicinity of experimental stations. The results concerned a standard of spring triticale determined as an average of varieties cultivated in a given year. It was stated that periods of drought of various intensity most frequently occur in spring in the period from sowing to tillering. Spring triticale endures dry periods well (50 < RPI < 74% or 75 < RPI < 89% of the norm; 0.4 < K ≤ 1.0), and the highest reduction in the quantity of spring triticale grain yield is caused by very and extremely dry conditions in the period from heading to wax maturity as well as in the whole period from sowing to wax maturity.