An electrochromic dimming device is provided. The electrochromic dimming device includes an electrochromic element (1), a color development power source (2), a color discharge powder source (3), and a variable resistance (4). The color development power source (2) supplies electric power to the electrochromic element (1) when the electrochromic element (1) develops color. The color discharge powder source (3) supplies electric power to the electrochromic element (1) when the electrochromic element (1) discharges color. The variable resistance (4) is disposed on a first current path without being disposed on a second current path. The first current path is formed from the color development power source (2) through a ground (GND) via the electrochromic element (1), and the second current path is formed from the color discharge power source (3) to the ground via the electrochromic element (1).