The invention discloses a method for detecting drug sensitivity rapidly. The method includes the steps of 1, mixing nutrient broth with antibacterials to prepare an antibacterial diluent with gradientchange in concentration; 2, preparing a standard bacterial suspension of strain to be detected with super pure water, and diluting the broth for standby use; 3, respectively adding the standard bacteria suspension diluted by the broth of the same volume in the antibacterial diluent prepared in the step 1, dropwise adding the obtained mixture to a sample plate of a mass spectrometer for sample application according to the concentration gradient of the antibacterial diluent, and incubating for 2.0-5.0 hours after sample application is completed; 4, after incubation, discarding the broth, drying, dropwise adding a mass spectrometry identification pretreatment reagent, performing microbiological identification with the mass spectrometer after crystallization and reading the result.The pretreatment operation of the method is simple, accurate drug sensitivity result can be provided more quickly and intuitively, and a certain reference can be provided for clinical guidance and rational use of drugs in a timely manner.