This paper illustrates the importance of safety testing of railway signaling computer control software in techniques and market development. A black-box testing scheme based on the current status is presented and key techniques to generate dynamic decision table are also introduced. Any kind of computer interlocking control software can be tested effectively by the universal testing platform demonstrated in this paper. And, testing results of the software of 10 stations are given. It is verified that the testing platform is useful in discovering software faults, improving the reliability and safety of software control, administrating the quality of development and production of railway computer real-time control systems and standardizing the computer interlocking market.