Abstract: A new way to design distant spacecraft formation flying in highly eccentric orbits is proposed, which simplifies the solution of the nonlinear equation of spacecraft relative motion rather than the equation itself. Under the assumption of equal period, the exact trajecotry of a random elliptic orbit relative to a circular orbit is obtained. The exact solution is expanded in Fourier series. It is proved that the term of single frequency is the dominant part of the solution. A new formula for formation design of distant spacecraft in highly eccentric orbits is deduced. A simulation of spacial circle formation is demonstrated. Design method with the new formula is explained step by step and the result is validated by numeric calculation. Since the assumption of close and near circular orbits is not used, the new formula is applicable to the formation design of distant spacecraft in highly eccentric orbits contrasting with C-W equation design method and orbital element method.