In order to enhance the intelligent level of substation secondary test and improve the test efficiency, the solution of smart substation testing based on intelligent speech recognition is proposed. A secondary speech recognition engine for power special lexicon is researched and the embedded system design of off-line recognition mode is given. In the laboratory and in the field, the intelligent terminal, protection device, merging unit and other equipment are tested by using the system. The experimental results show that the power special lexicon speech recognition engine significantly improves the overall recognition rate and stability and the speech control of the test system completes the whole test process accurately and correctly, which greatly enhances the maneuverability, flexibility and ease of use. This work is supported by Science and Technology Project of State Grid Corporation of China (No. 5211HZ1700A).