Present research in animal nutrition within the European region is looking for ‘home-made’ protein sources to avoid high dependency on imported soybean protein. The main objective of this study was, therefore, to investigate the potential for organic production of legume leaves as a protein source for pig nutrition. In 2017, production of leaves per hectare was estimated through forage sampling in the common stands of a lucerne (Medicago sativa L.) – red clover (Trifolium pratense L.) mixture growing under organic management. Number of stems, maximal stem length and leaf weight ratio on a DM basis was assessed for both species in the samples where total DM and leafproduction were calculated. Lucerne contributed more to the total annual DM yield of the mixture whilst red clover reached a significantly higher leaf weight ratio. Quality of leaves from bales of harvested hay seems to be acceptable for pig nutrition under organic management. This research has indicated that a lucerne – red clover mixture can be an effective field source of leaf protein.