Verification is one of the necessary steps to ensure the quality of nuclear power software, and benchmark calculation is an important mean of nuclear power software verification. The traditional methods of obtaining benchmark data mainly include independent experiments, collecting operation data of nuclear power plants, joining international experimental research programs, and purchasing data of international benchmarks. However, they have the problems of high cost and long cycle. In order to provide more benchmarks for the verification of steady state nuclear reactor core design programs, a benchmark derivation technique based on metamorphic testing principle is proposed in this paper. First, the technology established the framework of benchmark derivation, whose main idea is to directly calculate and solve the related input and output parameters of the original benchmark according to the parameters and relations of the metamorphic relationship, so as to obtain the derived benchmark (new test cases). Furthermore, aiming at the characteristic that the benchmark problems can input the data of the program under test in the form of a fixed format input card, an automatic derivation algorithm for benchmark questions was designed and a benchmark automatic derivation system was developed to improve the efficiency of derivation. Finally, the two-dimensional and three-dimensional benchmarks of the steady state neutron diffusion program were demonstrated as examples. Results show that the technology can automatically generate two-dimensional and three-dimensional derivative benchmarks in a single or batch way, which not only generates data accurately and efficiently, but also costs less than traditional methods.