An image color adjusting method comprising following steps: obtaining first pixel data of a plurality of pixels in an image in a first color space; performing a color space transforming process for the first pixel data to obtain second pixel data of the plurality of pixels in the image in a CIELAB color space, wherein each of the second pixel data includes a luminance component L*, a first color component a* and a second color component b*; performing the color space transforming process to the first pixel data to obtain fifth pixel data of the plurality of pixels in the image in the second color space; executing a skin color detection to the fifth pixel data to determine whether a skin color area exists in the image; adjusting the first color component a* and the second color component b* of the second pixel data to obtain third pixel data of the plurality of pixels, the image color adjusting method being characterized in that the step of adjusting the first color component a* and the second color component b* of the second pixel data includes: increasing the first color component a* and the second color component b* of the second pixel data to improve a color saturation of the second pixel data by a color adjusting model with a first setting of control parameters; and if the image includes the skin color area, adjusting the first color component a* and the second color component b* of a part of the second pixel data by the color adjusting model with a second setting of control parameters after the color saturation of the second pixel data is improved, and the part of the second pixel data corresponds to the skin color area in the image; and performing a color space transforming process for the third pixel data to obtain fourth pixel data of the plurality of pixels corresponding to the third pixel data in the first color space. obtaining first pixel data of a plurality of pixels in an image in a first color space; performing a color space transforming process for the first pixel data to obtain second pixel data of the plurality of pixels in the image in a CIELAB color space, wherein each of the second pixel data includes a luminance component L*, a first color component a* and a second color component b*; performing the color space transforming process to the first pixel data to obtain fifth pixel data of the plurality of pixels in the image in the second color space; executing a skin color detection to the fifth pixel data to determine whether a skin color area exists in the image; adjusting the first color component a* and the second color component b* of the second pixel data to obtain third pixel data of the plurality of pixels, the image color adjusting method being characterized in that the step of adjusting the first color component a* and the second color component b* of the second pixel data includes: increasing the first color component a* and the second color component b* of the second pixel data to improve a color saturation of the second pixel data by a color adjusting model with a first setting of control parameters; and if the image includes the skin color area, adjusting the first color component a* and the second color component b* of a part of the second pixel data by the color adjusting model with a second setting of control parameters after the color saturation of the second pixel data is improved, and the part of the second pixel data corresponds to the skin color area in the image; and increasing the first color component a* and the second color component b* of the second pixel data to improve a color saturation of the second pixel data by a color adjusting model with a first setting of control parameters; and if the image includes the skin color area, adjusting the first color component a* and the second color component b* of a part of the second pixel data by the color adjusting model with a second setting of control parameters after the color saturation of the second pixel data is improved, and the part of the second pixel data corresponds to the skin color area in the image; and performing a color space transforming process for the third pixel data to obtain fourth pixel data of the plurality of pixels corresponding to the third pixel data in the first color space.