Optical computerized tomography (OCT) has found wide applications in the noncontact detection of the flow field such as temperature filed, density field etc. However, the reconstruction of OCT is a projection reconstruction of incomplete data, and the algebra reconstruction technique usually adopted cannot solve the problem of reconstruction precision very well. A new kind of algebra reconstruction technique is presented. The property matrix including the prior knowledge is introduced. The fixed ultra-relaxation coefficient usually determined artificially is abandoned and an unfixed ultra-relaxation coefficient is adopted in the algorithm. The reconstruction results indicate that the algorithm with property matrix and unfixed ultra-relaxation coefficient can reconstruct the flow field of incomplete data satisfactorily, improve the reconstruction precision greatly, and match the measured results.