The invention discloses a micro-fluidic chip use method. The micro-fluidic chip has a seal space-type structure, a micro-fluidic channel is arranged in the seal space-type structure, two ends of the micro-fluidic channel are respectively provided with a liquid inlet and a liquid outlet, a lens aperture, a backlight aperture, parallel electrodes, a planar waveguide-type comb-type electrode and a capacitance-type dielectric electrode are orderly arranged along a direction from the liquid inlet to the liquid outlet and the side of the micro-fluidic chip is provided with an optical fiber through hole. In use, a microbe detection test solution enters through the liquid inlet, goes through the micro-fluidic channel and flows out of the liquid outlet. The lens aperture is connected to a microscopical hyper-spectrometer and a background light source is turned on and provides background light for the microscopical hyper-spectrometer through the backlight aperture so that microbe microscopical hyperspectral image information acquisition is realized. The capacitance-type dielectric electrode, the planar waveguide-type comb-type electrode and the parallel electrodes are respectively connected to a dielectric spectrum test device so that microbe dielectric properties and quantity are detected. The optical fiber through hole is connected to a fiber optic spectrometer so that microbe spectrum characteristics are detected.