This application provides a method for detecting a battery state of health. In the method, for a battery that does not supply power to a load within a time period, a detected unit is determined; an open-circuit voltage and a temperature of the detected unit are collected; a battery state of charge value and a loss capacity of the detected unit are obtained by means of calculation; and a battery state of health value of the detected unit is obtained by means of calculation according to a ratio of the loss capacity of the detected unit to an original capacity. This application further provides an apparatus for detecting a battery state of health. By means of technical solutions provided in this application, a deterioration degree of battery performance can be accurately monitored, and impact on a service is avoided.