Objective To explore the simultaneous determination of the contents of nine components in Xintong Oral Liquid using high-performance liquid chromatography-tandem mass spectrometry. Methods A Phenomenex Luna-C18 column (${250}\mathrm{\;{mm}}\times {4.6}\mathrm{\;{mm}},{5\mu }\mathrm{m}$) was used with acetonitrile-methanol-${0.02}\mathrm{{mol}}/\mathrm{L}$ammonium acetate as the mobile phase for gradient elution at a flow rate of${0.9}\mathrm{\;{mL}}/\mathrm{{min}}$. Mass spectrometry conditions: ESI source, MRM mode, quantification was performed using the peak area of the quantitative ion pairs. Results The linear ranges of the nine components, including ferulic acid, diphenylethylene glycoside, puerarin, etc., were from 15.22 to 15220 ng/mL to 25.36 to${25360}\mathrm{\;{ng}}/\mathrm{{mL}}$. The recovery rates were from 98.15% to 101.84%, with RSDs ranging from 0.67% to 1.64%. In nine batches of samples, the mass concentration ranges of the nine index components were from 0.180 to 4.699 mg/mL. Conclusion This study innovatively applies the HPLC-MS/MS technique to efficiently and accurately determine the nine core components in Xintong Oral Liquid, simplifying the process, accelerating quality control, and aiding in standardized production.