Abstract: Stress distributions in single Pin-loaded Composite plates have been investigated by using a new method——Coating Moire lnterferometry,which was set up in Tianjing University.Moire Fringe patterns in the directions of 0°,45° and 90° have been obtained.Fixtures were improved in order to eliminate rigid body displacements produced in experiments.And the stiffness matrix to the specimen materials wero obtained through experiments and calculations.From the Moire fringes, distributions of strains and stresses were presented on horizontal sections through the centers of holes,vertical sections near holes and vertical symmetrical sections under the lower part of the holes. Six kinds of composite specimen, which consist of different fibers and layers,were investigated.Stress concentration factors near holes were also determined.Equations of equilibrium were checked to examine the precision of the experiments, and the reasons on experimental errors were explained. It is confirmed that Coating Moire Intarferometry cams be used in the determination of the stress distribution in Single Pin-Loaded Composite Plates.