The research was conducted in the greenhouse of Institute of Soil Science and Plant Cultivation in Puławy. The aim of the study was the estimation of changes in the growth, development and dynamics of dry matter accumulation course of faba bean plants grown from seeds treated with magnetic field prior to sowing. The factor of the first order were two faba bean varieties: Nadwiślański – a traditional form and Tim – a determinated form, while the factor of the second order were exposure doses of magnetic field intensity: D1 – 10750 J m-3 s (B = 30 mT, s = 15 s), D2 – 85987 J m-3 s (B = 85 mT, s = 15 s) and D0 – without stimulation (control). Seed treatment with magnetic field positively affected plant emergence, modified the course of individual faba bean developmental phases, and had a significant effect on dry matter accumulation rate in particular plant organs and on their size. The highest effect of this treatment on the increase of vegetative organs dry matter yield had place at flowering and pod setting period, and in the case of the generative organs – during seeds filling and maturation of pods.