Abstract: OBJECTIVE To investigate the compatible stability of tropisetron hydrochloride injection with 7 different infusions. METHODS According to the clinical application of dose, tropisetron hydrochloride injection was mixed with 7 different injections included Fructose injection, 0.9% Sodium Chloride injection, sodium lactate ringer’s injection, 5% Glucose injection, Compound Sodium Chloride injection, Glucose Saline injection and Invert Sugar injection at room temperature, the compatibility content was determined by liquid chromatography tandem mass spectrometry. Color, pH, particulates contents of tropisetron was also studied. RESULTS The content, pH and color of tropisetron hydrochloride solution showed no significant change in the initial state, the number of insoluble particles(≥10 μm and ≥25 μm size) were acceptable. CONCLUSION Tropisetron hydrochloride injection was stable for up to 4 h in vitro in 7 different solutions at room temperature.