The following fertilizers were applied in the field experiment set on the podzolic soil developed from light loamy sand: slops, sugar factory lime, sawdust from sawmill and from works, mineral fertilizers, farmyard manure and straw. Chickling vetch (Derek cv.) was used as a testing plant in the first year of experiment. The yield of chickling vetch seeds as well as the total and specific protein content, and amino acid composition were determined after harvest. Wastes applied significantly affected the yield of the tested plant, slightly differentiated the total protein content and the more specific one. All wastes contributed to the changes of particular amino acid content, notably cysteine, tryptophan and histidine. Sawdust decreased methionine, serine, alanine, glycine and leucine and increased the valine and lysine levels. Slops used along with the straw influenced on the increase of amino acid contents more positively than the slops alone. The farmyard manure's effects on amino acid composition of protein could be comparable to the sugar factory lime and the lime with sawdust.