Legume-cereal mixtures cover a considerable cultivated area in Poland what follows mainly from better and more stable yielding of mixed stands than pure ones. Besides a very good protein fodder the legume – cereal mixture can leave also good stand for subsequent plant. It is an effect of symbiosis of legumes with symbiotic bacteria and thanks to that lower doses of nitrogen are used in the mixture stands and fixed nitrogen is also available in the soil to the subsequent plants. This kind of cultivation become a very good part of ecological agriculture rules where due to forbidden nitrogen fertilizers use, this nitrogen fixed symbiotically is of great importance. The aim of studies was to recognize a residual effect of the forecrop which were: pure sowing of lupine, lupine and barley mixture and pure sowing of barley, on yielding of winter wheat. Studies were led at the Agricultural Experimental Station in Grabów, which belongs to the Institute of Soil Science and Plant Cultivation – State Research Institute (IUNG-PIB) in Puławy. Winter wheat var. Arkadia was sown after blue lupine var. Regent which was cultivated in the pure stand and in the mixture with spring barley var. Johan. Wheat plant density amounted to 5,5 mln plants per hectare, and area of plots to harvest - 24 m² . Before harvest selected biometric measurements of plants were performed and, after the harvest in the full maturity, yield and features of its structure as well as chemical content of winter wheat grain were determined. It was found a favorable effect of forecrop on yielding and features of winter wheat yield structure (e.g. number of ears, number of grain per plant and 1000 grain weight). The influence of forecrop on the level of winter wheat yielding depended to a large extent on weather conditions course in the experimental years and on blue lupine variety as well as composition of lupine – barley mixture. In years unfavorable for winter wheat cultivation the difference between yields of wheat cultivated after good and weak forecrop was greater than in the years with favorable weather course.