Abstract: Through thoroughly analyzing the Experts Graded Method in the book of《Pipeline Risk Management Manual》written by Mr.W.Kent Muhlbauer,some illogical problems are discovered in some aspects.Based on some improvements and amendments about these problems,a new algorithm model of Semi-quantitative Experts Graded is put forward,which is adapted to the facts in China.And basic principles for establishing evaluation system,acceptable risk value,risk adjust precept,which used in the process of pipeline risk are also put forward,therefore,the practicability and objectivity of using Semi-quantitative Experts Graded Method to evaluate pipeline risk will be advanced.