The invention provides a health state assessment method of a retired electric automobile power cell. The method comprises the steps of: carrying out basic performance detection, cell key performance sampling detection and cell internal characteristic detection on the retired electric automobile power cell, wherein the basic performance detection comprises cell appearance detection, cell open-circuit voltage and internal resistance detection, cell capacity and energy detection, and cell charge retention detection; the cell key performance sampling detection comprises cell life characteristic detection, cell environment adaptability detection, cell multiplying power characteristic detection and cell safety performance detection; and the cell internal characteristic detection comprises electrode slice form and material combination condition analysis, diaphragm form and aged condition analysis, material crystal structure analysis and composition analysis, material available capacity and electrochemistry cycling performance analysis, and electrode surface solid electrolyte interface analysis. By adopting the method, the basic parameters of the cell are comprehensively detected, sampling detection is carried out on the key parameters and internal characteristics of the cell, and the health state of the cell is accurately evaluated.