Abstract: The application of the rock breaking technique with premixed abrasive water jet to the hard rock tunnel boring machine (TBM) is expected to solve the problems of low efficiency and high cost of traditional rock breaking with the disc cutter when high strength rock is tunneled during tunnel construction. However, rock breaking with the premixed abrasive water jet is affected by many factors and the system is complex, and its application in TBM rock breaking and tunnelling field is not mature enough. By making use of the comparative research method and the rockbreaking experimental device with high-pressure water and sand, the comparative tests are performed for fixed sprinkler at fixed time and mobile sprinkler at a constant speed, to study the influence of different hydrostatic pressure, injection distances and moving state of the sprinkler on the average consumption of abrasive, the depth and the width of the rock-breaking pit. For the rock-breaking width, these factors are sorted by their influence: moving state, injection distance and hydrostatic pressure. For the depth of rock breaking, these factors are sorted by their influence:movingstate,hydrostatic pressure and injection distance. By exploring the best rock breaking parameters of the premixed abrasive water jet technique, a basis is provided for the research of TBM-based new rock breaking techniques.