A method for evaluating skin tissue includes: obtaining a tomographic image of skin； performing a quantization process for quantizing brightness values of the tomographic image of skin to generate a quantized image； performing a binarization process on the brightness value of each image point in the quantized image according to a first threshold interval to generate a first filtered image； performing the binarization process on the brightness value of each image point in the quantized image according to a second threshold interval to generate a second filtered image； obtaining a first estimated tissue boundary according to the distribution of the bright spots in the first filtered image； obtaining a second estimated tissue boundary according to the distribution of the bright spots in the second filtered image； estimating a thickness of skin tissue according to a difference between the first and second estimated tissue boundaries.
