Grain yield and quality as well as the weed infestation of winter wheat grown after potatoes, peas and winter wheat were evaluated in the study. The experiment was established in a system of randomized blocks, in three replications. The experimental results were statistically processed via the analysis of variance method. Coefficients of Pearson’s linear correlation between grain yield and its components, grain quality parameters, and the number and air-dry weight of weeds were also calculated. Grain yields of winter wheat were higher when it was grown after potato and pea than after winter wheat. In addition, winter wheat grains harvested from plots with potato and pea as previous crops had a higher total protein content and a higher sedimentation index than those harvested from plots with winter wheat as the previous crop. However, the study years affected the protein, gluten and starch contents of winter wheat grain to a greater extent than the previous crops did. A higher number of weeds with a higher air-dry weight was recorded on the post-winter wheat than on the post-potato and post-pea plots. Negative values of correlation coefficients were computed between the number of weeds and their air-dry weight and grain yield, number of spikes, grain weight per spike, 1000 grain weight, total protein content of the grain, and the value of sedimentation index as well as between weed number and wet gluten content of the grain.