1. ABSTRACTKOMATSU has successfully developed and marketed the HYPER GX series computer-controlled, intelligent hydraulic excavators. The development concepts of the HYPER GX series are as follows: 1.To improve safety at construction sites by use of measuring functions which reduce the number of ancillary workers. 2.To improve working environment and the quality of work by use of automatic functions which reduce operator fatigue and time required to complete a job. 3.To solve the problem of shortage of experienced workers by the use of operator support functions which allow easy operation even for inexperienced or older operators. Representative of these is the fully automatic grading function, with which the movement of boom, arm and bucket is computer-controlled to enable automatic excavation at a predetermined gradient. Here, the operator simply needs to press a switch, allowing even inexperienced operators to execute straight digging easily and without fatigue, usually a very difficult operation requiring substantial experience.Additionally, the machine is equipped with 12 newly developed advanced functions, such as bucket monitor, electrically cushioned cylinders and soft mode (for shock-free movement). This machine is currently being used throughout Japan in a variety of jobsites where it enjoys a high reputation.This paper presents the development concepts, configuration, functions and advantages of the HYPER GX hydraulic excavator.