Abstract: The pipe leak detection method based on ITA（Inverse Transients Analysis）was studied in this paper.The problem of pipe leak detection was converted to optimization problem.Taking the leak location and leak size as decision variables,the optimization model,in which the object function was to minimize the sum of square difference between calculation and measured value,was established.The GA（Genetic Arith-metic）,in which the 1-D approximation Vardy-Brown model was used to calculate fitness value,was applied to solve the optimization model.The feasibility of this method was validated by experiment.Moreover,through analyzing the main influence factors for the method,this paper pointed out that the detection result was impressible to the water hammer wave speed.