Abstract: OBJECTIVE To identify an unknown dithio-carbodenafil analogue illegally adulterated in health foods. METHODS An unknown dithio-carbodenafil analogue was observed in a routine screening for compounds illegally adulterated in heath foods by HPLC-DAD. The compound of interest was isolated by silica gel TLC. Its quasi-molecular ion and MS² fragmentation spectrum were obtained by UPLC-MS/MS, and its ¹³C-NMR and ¹H-NMR spectum were also obtained using nuclear magnetic resonance. Its structure was elucidated by analysis of these data in combination of the literature. RESULTS A new dithio-carbodenafil analogue, which structural was 3,5-dimethylpiperazinyl dithio-desmethyl carbodenafil, was detected in health foods. CONCLUSION It is a new compound illegally adulterated in health foods. The current inspection standard, which lists 13 target compounds, does not include this compound.