Abstract: An indirect tensile strength tester based on elastic theory is developed for decreasing the influence of self-weight and non-homogeneity on indirect tensile strength of geomaterial. Water pressure is imposed on the inside of the ring specimen to cause tensile failure.As water pressure is imposed,uniform radial tensile stress is produced along the inner side of ring specimen and crack will be appeared in the weakest direction of ring specimen.A relationship among tensile strength,dry unit weight and water contents of compacted loess are proposed.The test results show that the tester is reliable and easy to operate.