A color temperature adjusting device of a light source module is revealed. The light source module includes at least one light source and at least one electrochromic device arranged at one side of the light source with a light emitting surface. The light source module is electrically connected to a control module. The control module consists of a light-source driver circuit and a control circuit for electrochromic devices that controls colored/bleached state of the electrochromic device. The light-source driver circuit is used to drive the light source to emit light. After passing through the electrochromic device, a light source is turned into a warm color light source or a cool color light source.