In virtue of educational ecology,Foreign Language Economics and Interdisciplinary education,the paper divided busi- ness English knowledge and skills into three parts by course communities,confirming immersion and complicated relationship,that is some assistance and countervailing force. They exist in intercrossing ecology mode no matter in course communities or economic envi- ronment. So Three - discipline Intercrossing educational ecology concept is established to deal with the inter - relationship,compete ra- tionally and form a dynamic,balance ecological educational mode.