A fully automatic online aero aluminum sorting and recovery system based on LIBS technology, comprising: a sample feeding unit consisting of a vibrating plate and a chute that is mounted at an outlet position of the vibrating plate, a surface treatment unit, a material positioning unit, a three-dimensional morphology scanning sensor; a cable; a LIBS analysis and detection unit consisting of a pulse laser, a laser light path, a fiber optic spectrometer and a computer provided with a LIBS analysis software, a transfer unit consisting of a stepper motor, a conveyor belt arranged in a loop form and a tray and a sorting and recovery unit = configured to perform automatic sorting and recovery of aluminium samples of different grades and comprises a delivery system, and a pneumatic device, the delivery system includes baffles, chutes and baskets, wherein the sample feeding unit is connected to the transfer unit via the chute of the sample feeding unit and said chute is configured to slide arranged samples onto said conveyor belt; the stepper motor is configured to drive the conveyor belt; the surface treatment unit is arranged at a rear end of the sample feeding unit, so that the surface of the samples can be quickly treated by the surface treatment unit, and the transfer unit is configured to transfer the treated samples from the surface treatment unit to the material positioning unit; the material positioning unit is configured to scan profile information of the treated samples by the three-dimensional morphology scanning sensor and to transmit this information to the LIBS analysis and detection unit via the cable; the transfer unit being further configured to transfer the treated samples from the material positioning unit to the LIBS analysis and detection unit which, upon receipt of a synchronization signal from the material positioning unit, is configured to emit laser light according to the speed of the conveyor belt when the treated samples pass to irradiate and excite the surface of the treated samples, the fiber optic spectrometer is configured to receive a spectral information produced by the irradiated and excited surface of the treated samples for collecting and processing the spectral information so as to determine sample grade information of the treated samples; the transfer unit is configured to transfer the treated samples from the LIBS analysis and detection unit to the sorting and recovery unit, and based on the determined sample grade information, the chute of the sorting and recovery unit is configured to slide the treated samples into respective baskets, wherein the samples are aero aluminium samples having an oil, paint, or coating layer, wherein the surface treatment unit is configured for treating the surface of the aero aluminum samples having an oil, paint, or coating layer, to obtain a smooth and clean detection surface, the surface treatment unit consisting of photoelectric switches, a signal line, a clamping device and a high-speed grinding device; the photoelectric switches are mounted on both sides of the conveyor belt upstream of the clamping device and are configured to block when a sample to be treated passes and to supply said information via the signal line to the clamping device; the clamping device is configured to fix the sample to be treated in the center of the tray when the sample arrives; at the same time, the high-speed grinding device directly above the clamping device is configured to fall down and grind off the oil, paint or coating layer on the sample surface, with a grinding thickness not less than 500 μm, so that the sample surface to be detected becomes a smooth and clean aero aluminium surface.