In 1997-1999 observations of health status of spring barley grown in two-component mixtures with cereals or pea were performed in two experiments, differing in the agricultural utility of soil. A much better health status of the studied species was found in the mixed crop than in their pure stand. Two-component mixtures were differentiated in the occurrence of leaf diseases caused by Drechslera teres, Drechslera graminea, Puccinia graminis and P. hordei, Rhynchosporium secalis and Erysiphe graminis. The healthiness of lower parts of stem and roots depended on the quality of soil and mixtures factor. A higher infection due to foot root rot complex was noted on barley cultivated on the poorer soil in homogenous stand.