Abstract: The 3D printing technology is widely used in medical, aerospace, automotive, construction and other fields. This paper applies a 3D printing technology to the field of rock mechanics experiment. With the 3D printing, two types of gypsum specimens are produced for the laboratory uniaxial compression test, and it is shown that the 3D printing technology can produce the required complex size of the specimens. The 3D printing gypsum specimens enjoy low strength and high plasticity. The mechanical properties of simple standard specimens are found to be reproducible but the mechanical properties of the complex specimens are not; and the production of the specimens with cracks still has technical difficulties.