The article presents the results of an environmental quality assessment conducted using the phytoindication method. This approach is based on measuring the bilateral asymmetry of leaves of two oak species: the holm oak and the long-stem oak. A statistical analysis was performed to track changes in the bilateral asymmetry of selected morphometric traits of these oak species' leaves. For each oak species, samples were taken from two different environments that varied in levels of environmental pollution. ANOVA, two-way T-test and test were performed separately in the MAPLE software package for each environment. We built a regression model for both plants in both environments to determine how the bilateral asymmetry depends on the leave length. It was observed how the tendency coefficients there changed depending on the environment.