Abstract: A new concept of spacecraft sparse formation flying and its design method are presented in this paper. Differences between the new concept and the widely accepted spacecraft compact formation flying are explained, and possible application prospects of sparse formation flying are described. A new formula that is more widely applicable than Hill's solution is proposed for the design of sparse flying formations, and several sparse formations are derived. In the case that distances between formation spacecrafts are very closed, the new formula become naturally the same as Hill's solution. Advantages of the new formula are illustrated clearly by calculating one simple example.