The effect of soaking the seeds in solution of selenium (Se) and foliarly spraying with Se on Phaseolus vulgaris cv. Stanko and Topolovec were studied. The flows of electrons in the photosynthetic apparatus and in the respiratory chain were measured in control plants and in plants developed from selenium treated seeds and in once and twice foliarly treated plants. Yield of control and treated plants was measured at the end of experiment. The respiratory potential of Phaseolus vulgaris, measured by electron transport system (ETS) activity in cv. Stanko, significantly increased in selenium treated plants. The potential and effective photochemical efficiency of photosystem II were similar comparing treated and untreated plants. The addition of selenium induced yield in twice Se foliarly treated plants in both cultivars growing in greenhouse.