In ultrasonic computerized tomography (CT) imaging test of concrete structures, the stability and accuracy of the imaging results were still difficult to meet practical demands.A CT imaging technology based on simulated annealing genetic algorithm (SAGA) is presented here to solve the problems.Firstly,a natural weight matrix with clear physical meaning was introduced in the inverse algorithm to form the quadric broadening objective function according to the propagating character of ultrasound in concrete. And then the simulated annealing searching is added to speed up inverse process and improve the convergence and stability of the algorithm.And finally,the optimal inverse imaging results could be achieved by variable ectopic adaptive genetic algorithm.It is shown from numerical simulation experiment that because of contribution with the usage of the correct priori information and the excellent characteristic of the SAGA in searching the global minimum value of function,the calculated results are accurate and effective and the numerical value is stable,and the imaging results reflects the inner defections of the tested object reliably and exactly and image resolution is improved obviously.