The invention discloses a method and a system for desalting and backwashing through electric absorption, belonging to the field of water treatment. The invention aims at solving the problem that the prior art can not ensure both the regeneration effect of an electric absorbing module and higher water yield. The method comprises the following steps of: backwashing the electric absorbing module by water recycled in the previous period, re-backwashing the electric absorbing module by raw water, and recycling water obtained by backwashing through the raw water for backwashing in the next period. The system comprises an electric absorbing module to be regenerated, a recycled water tank, a recycled water backwashing unit, a raw water tank, a raw water backwashing unit and a recycling water unit. By increasing the steps and units on the basis of the prior art, the invention realizes both the regeneration effect of the electric absorbing module and the higher water yield.