Researches were conducted in the vegetation hall of Institute of Soil Science and Plant Cultivation – State Research Institute in Puławy. Plants were cultivated in Mitscherlich pots containing a mixture of soil - 5 kg and sand - 2 kg per pot. Yellow lupine variety: Dukat and Taper was the first row factor, and the second one - type of water used for plant watering: Wk – non-magnetised water (control), Wp – water conditioned by flow magnetizer, and Wn – water conditioned by fishplate magnetizer. The aim of undertaken studies was to evaluate magnetically conditioned water influence on seed germination as well as growth, development and yielding of lupine. It was found that magnetically conditioned water increased lupine germination. It concerned both the time and the dynamic of plant emergence. Plants watered with magnetically conditioned water achieved greater absolute growth rate (GR) and relative growth rate (RGR) than plants watered with normal water. The use of magnetic water caused significant seed yield increase of both lupine varieties. Yield increase was a consequence of greater number of pods per plant and greater number of seeds per plant, since the thousand seeds mass did not undergo greater change.