This book LNCS 16481 constitutes the refereed proceedings of the 7th International School on Engineering Trustworthy Software Systems, SETSS 2025, held in Beijing, China, in May 17&23 , 2025. The 7 full papers were carefully reviewed and selected from 8 submissions. The proceedings focuses on lectures given during SETSS covered an ample variety of techniques to achieve this goal, from model checking to simulation testing, from the use of formal methods and contracts to model-based engineering.