Purpose of the study: to study the effect of oil pollution on the morphological parameters of cereal grasses: canary grass, timothy grass and meadow fescue. Tasks: assessment of the impact of oil pollution of soils on seed germination, growth and development of the studied species by morphological parameters; analysis of the species variability of the studied indicators. Oil-contaminated high-moor peat was used as a substrate. Objects of research: seeds of cereal grasses: meadow timothy <i>Phleum pratense</i> L, 1753, meadow fescue <i>Festuca pratensis Huds</i>, canary grass <i>Phalaris</i> <i>canariensis</i>. Evaluation of the effect of oil-contaminated soil was carried out on the basis of changes in seed germination and morphological parameters: plant mass, leaf length, length and number of roots. The experimental results were processed by the method of variation statistics. As a result of studying the effect of oil-contaminated peat on seed germination, it was found that in the variants of the experiment with the minimum oil content, no differences were noted with the control values. The maximum concentration of oil (10,000 mg / kg) reduced seed germination by 9–24%. With an increase in the oil content in the soil, the morphometric parameters of all the studied species of cereal grasses also decreased. The greatest differences in the studied test functions, in comparison with the control variant, were noted in canary grass, the smallest – in meadow fescue.