Stress resistance is an important pre-condition of successful soybean production in demanding agroecological conditions. Among different types of abiotic stress, drought, temperature and salt stress are the most prominent. This PhD dissertation aimed to investigate some of the physiological mechanisms of soybean response to the above mentioned stresses. The research was performed with 6 cultivars in the germination - emergence stage and two cultivars in the flowering stage. In the first experiment, soybean seed was germinated in paper towels soaked with water or the solution with given osmotic pressure. Two levels of drought (5% and 10% PEG solutions), salt (50 and 100 mM NaCl solutions) and temperature stress (10°C and 30°C), as well as control treatment (20°C, water) were applied through a 7 days germination period. Beside the evaluation of the seed germinability (%) at the end of the treatment, seedling and hypocotyl masses, the content of hydrogen peroxide, proline, phenols, the lipid peroxidation rate were determined, as well as total and specific activity of ascorbate peroxidase, catalase, guaiacol peroxidase and glutathione reductase in hypocotyl tissue were analysed. The highest stress effect in the germination stage had a higher level of drought stress (10% PEG) and low temperature (10°C). High temperature (30°C) was favourable for seedling development and mild drought stress (5% PEG) have had a “priming” effect and increased germination rate. In the second experiment, selected two cultivars were grown in the pots, filled with soil and kept in the open until the flowering stage (R2), and afterwards exposed to different temperature conditions (30°C, 10°C and 20°C as control treatment) during 3 days in a climate chamber. The contents of photosynthetic pigments, photosynthesis efficiency parameters and all the aforementioned physiological indicators of plant response to stress were determined in the most developed trifoliate leaf. Highly significant treatment influence on the analysed parameters in the both growth stages, confirms that the applied treatments invoked the oxidative stress and defence reactions in soybean at molecular level. In general, the total activities of tested enzymes were higher at 10°C in germination stage, and at 30°C in flowering stage, which suggests a diversity of stress effects of ambient temperature depending on the growth stage in soybean.