Automated testing of technological software for computer-based interlocking systems is of critical importance in ensuring the safety of railway traffic. Introduction: as the CBI software components become more complex, so manual testing methods are no longer adequate. Purpose: to develop an automated testing system for the CBI software based on a scripting approach that ensures the overall verification of functional requirements and the correctness of the algorithms. Methods: a hybrid approach combining the Lua scripting language for describing test scenarios, a virtual environment for simulating the operation of outdoor equipment, automatic test generation, and the integration with an expert protocol analysis system. Results: a modular testing system that includes a library of test scripts, an interpreter with a specialized API for interacting with the computer software, and automatic validation mechanisms have been designed. Practical significance: the approach demonstrated its effectiveness in real CBI configurations. The development directions have been outlined as follows: integration with CI/CD and expansion of coverage with fault tolerance tests. Discussion: the research has revealed the advantages of the script approach. These include the independence of tests from a specific station and the possibility of reusing scripts.