The invention discloses a corrosion detection method for insulator hardware based on laser-induced-breakdown spectroscopy. The method comprises the following steps: S1, acquiring plasma spectral dataof insulator hardware with different corrosion degrees; S2, pre-processing the plasma spectral data; S3, acquiring an evaluation model of a corresponding relationship of the insulator hardware and thecorrosion degrees; S4, acquiring plasma spectrum of the to-be-detected insulator hardware and pre-processing the plasma spectrum; and S5, taking the plasma spectrum data of the pre-processed to-be-detected insulator hardware as input data of the evaluation model of a corresponding relationship of the insulator hardware and the corrosion degrees to obtain the corrosion degree of the to-be-detectedinsulator hardware to detect corrosion of the insulator hardware. The method detects corrosion of the end hardware of the insulator accurately in a non-contact manner. Compared with a conventional detection method, the method achieves online detection, and is simple in detection flow and reliable in result, and the detection process is simplified greatly.