Abstract: The tensile, compressive and shear property of 4D in-plain C/C composites in each direction were studied by macroscopic mechanical experiment. ARAMIS incontact strain test system was successfully used to solve the incompatible problems produced in using strain gauge to test the properties. The results show that the properties of the 4D in-plain C/C composites exhibit anisotropy, double modules and the nonlinear characteristics. Under tensile load, the specimens show crack delamination growth along the radical direction, and show carbon rod pulled out along the axial direction. Under compress load, the specimens show shear failure caused by the increment of ductility. It embodies brittle in tensile and pseudoplastic in compress. The specimens show delamination failure in xz plane under shear load, and fiber bundle pulled out in xy plane.