Interfacial engineering is an efficient and versatile strategy to accelerate the catalytic performance of functional nanomaterials. Herein, we have constructed ternary titanium dioxide (TiO2)@molybdenum disulfide (MoS2)/cobalt ferrite (CoFe2O4) composite nanofibers via a two-step hydrothermal reaction. Firstly, MoS2 nanosheets are grown on TiO2 nanofibers, then acting as an interfacial barrier to load ultrafine CoFe2O4 nanoparticles. Thanks to the synergistic effects among the interfacial interactions between MoS2 and TiO2 as well as CoFe2O4 component, the prepared ternary TiO2@MoS2/CoFe2O4 composite nanofibers displayed much better catalytic activity than any single and bicomponent composite nanofibers for peroxidase mimicking. Due to the superior catalytic efficiency of the ternary TiO2@MoS2/CoFe2O4 composite nanofibers, a highly sensitive way for L-cysteine sensing was developed. Our work offers an advanced surface engineering solution to construct a peroxidase-like catalyst to detect L-cysteine, with bright future in environmental science and biological technology.