Abstract: Height measuring by master satellite and concomitant satellite formation InSAR system being the background,the problem of the concomitant satellite formation configuration optimal design is studied.Firstly,the criterionof optimization is defined as maximumtime ratio of effectual observationwhich describes the measurement performance in a whole orbit period. Correspondingly the CartWheel-like satellite formations are focused on,in which satellites are in the same concomitant orbit around the virtualcenter with symmetrical distribution.The ratioof two amplitudes and the difference of two phases in relativemotion are served as variables of optimization.By a numerical simulation a figure is found out,which shows the relation between the criterion of optimization and the variables of optimization.The orbit elements of the satellites in the best configuration are provided. Then the method estimating fuel consumption for formation keeping and orbit maintaining is given and the necessaryfuel mass of the best configuration for a period one year is calculated.Last a beneficialconclusion is drawn,which will be of some help to the optimizationof whole InSAR system.