The Supersymmetric Standard Models with Decaying and Stable Dark Matters Xin Gao, 1 Zhaofeng Kang, 1 and Tianjun Li 1, 2 $^{1}$Key Laboratory of Frontiers in Theoretical Physics, Institute of Theoretical Physics, Chinese Academy of Sciences, Beijing 100190, P. R. China We propose two supersymmetric Standard Models (SMs) with decaying and stable dark matter (DM) particles. To explain the SM fermion masses and mixings and have a heavy decay DM particle S , we consider the Froggatt-Nielsen mechanism by introducing an anomalous U (1)$_{X}$ gauge symmetry. Around the string scale, the U (1)$_{X}$ gauge symmetry is broken down to a Z$_{2}$ symmetry under which S is odd while all the SM particles are even. S obtains a vacuum expectation value around the TeV scale, and then it can three-body decay dominantly to the second/third family of the SM leptons in Model I and to the first family of the SM leptons in Model II. Choosing a benchmark point in the constrained minimal supersymmetric SM with exact R parity, we show that the lightest neutralino DM is consistent with the CDMS II experiment. Considering S three-body decay and choosing suitable parameters, we show that the PAMELA and Fermi-LAT experiments and the PAMELA and ATIC experiments can be explained in Model I and Model II, respectively. PACS numbers: 12.60.Jv, 14.70.Pw, 95.35.+d 1 Abstract $^{2}$George P. and Cynthia W. Mitchell Institute for Fundamental Physics, Texas A & M University, College Station, TX 77843, USA (Dated: June 7, 2018) arXiv:1001.3278v2 [hep-ph] 31 Aug 2010