Abstract: The velocity change of negative pressure wave generated by pipeline leak during the process of trans-mission is analyzed,the formula of wave velocity changing with temperature is deduced,and the pipeline leak position-ing problem is transformed into a function optimization problem.Based on this deduction,an adaptive immune algorithm is put forward and is used to solve the pipeline leak positioning problem.Actual example calculation shows that the adaptive immune algorithm is superior to both genetic algorithm and normal immune algorithm in solving the optimal problems,and it can solve the leak positioning problem effectively.