Abstract: In order to research the related substances of dabigatran etexilate mesylate, seven related compounds were synthesized and the related detection methods were established(Using XBridge C₁₈ as the column, methanol-0. 01mol/L potassium dihydrogen phosphate as the mobile phase Gradient elution, detection wavelength of 310 nm). The solvents and the injection volume were also screened. Results showed that the established method could separate the dabigatran etexilate mesylate and seven compounds completely, and the reproducibility was good and the accuracy was high, which was suitable for the detection of the related substances of dabigatran etexilate mesylate.