Abstract: Most of the CERs(Cost Estimation relationship)available for satellites have been unsuited for smallsats,with the estimated costs being much higher than the actual ones,because of great reduction of the smallsat costs.The paper describes the SSCM (Small Satellite Cost Model) of CER derived on the basis of the history data of the costs of 29 small satellites developed and launched in recent years and gives a calculated example,in which the unit of cost is converted into yuan (RMB).Finally,some CERs with two independent variables are given.