Abstract: In recent years, soil degradation was becoming seriously in the farming-pastoral zone in Inner Mongolia, and grain-forage production structure was becoming imbalanced. In order to promote the coordinated development of grain-forage industry and improve the soil properties, oat was intercropped with common vetch and alfalfa in saline land and chernozem. The width of oat was 1.2, 2.4 and 3.6 m, and the width of common vetch and alfalfa was 1.2 m, in other words, the intercropping patterns were 1:1, 2:1 and 3:1. The forage yield and quality, and activities of soil catalase, sucrase, urease enzyme were measured. The results showed that forage yield of 2:1 pattern increased by 7.95%-30.78% and 10.05%-38.09% in saline land and chernozem, respectively, and the forage quality of 2:1 pattern was significantly higher than that of other patterns. Soil catalase activity of 2:1 pattern in saline land and chernozem was 5.30%-38.40% and 0.62%-24.89% higher than that of other patterns, and sucrase activity of 2:1 pattern in saline land and chernozem was 0.15%-43.66% and 0.23%-22.84% higher than that of other patterns. The urease activity of 2:1 pattern in oat land was the highest due to the higher using efficiency of nitrogen. In one word, the intercropping pattern of 2:1 is an ideal practice pattern both in saline land and chernozem.