Abstract: Boarding crop seeds on recoverable satellites to induce novel variety has become an important characteristic of space mutation breeding. It is a new breeding technique, using a special space environment on seeds, which could cause the release of chromosomal aberration and gain favorable gene mutation to breed new varieties in ground. Space mutation breeding has been widely used on the many crops and vegetables, such as wheat, rice, pepper, tomato and 72 varieties have been identified by nation or provinces. China leads the world in space breeding, but the research on pasture space breeding is still in its initial stages with a focuse on the alfalfa. This paper briefly elaborated the space mutation breeding on alfalfa and the current problems.