The parallel computer programs to solve time-dependent two dimensional neutron transport problem were drawn up, and many test calculations were completed by using the YH-l type electronic computer. The calculations for the six critical assemblies show that the discrepany between the calculation value and the experimental result of the critical parameter is less than the experimental error of the data. This proves that the computer programs are effective. The validity of the programs is also verified by the fact that al1 calculation results of the different parallel algorithm are identical. The，calculations show that the efficiency of the parallel computing is roughly thirtyfold of that of the serial program when the data are the same. To enhance the efficiency of the parallel computing, we developed a combining dimension technique and an oblique diagonal sweep method in addition to using the general parallel technique.