Abstract: A power-off protection circuit and a power-off protection method of an electrochromic device are revealed. A compelling bleached unit is connected to two electrodes of an electrochromic element in parallel. When a power provided to the electrochromic element is turned off, the compelling bleached unit forces the electrochromic element to be bleached by creating a short circuit in the electrochromic element. Thus quality of the electrochromic element will not be affected by the condition that the electrochromic element remains colored and unable to be bleached when the electrochromic element is still in the colored state and the power is suddenly cut-off.