Aim: Fulminant myocarditis (FM) has neither validated biomarkers nor well-established therapy. Roles of tRNA-derived small RNAs (tsRNAs) in FM remain unknown. Materials & methods: Small RNA sequencing was conducted in plasma from children with FM during acute and convalescent phase and matched healthy volunteers. Data were validated by quantitative real-time PCR in larger sample-sized groups and in vitro. Functional analysis was performed to explore the roles. Results: tiRNA-Gln-TTG-001 was overexpressed in children with FM during acute phase, and the generation and extracellular release of tiRNA-Gln-TTG-001 were higher after myocarditis-mimicked activity in vitro. Several pathways might participate in the pathogenesis of FM. Conclusion: tsRNAs may play an important role in FM, and tiRNA-Gln-TTG-001 might represent a novel and promising biomarker and therapeutic target.