An algorithm based on the cell image center of gravity and its scaleless range (as scale-invariant) is proposed to estimate the fractal dimension of the marrow cell images. Since the texture of a color image contains not only certain statistical similarity on the structure but also the color distributions, two color parameters are extracted from the color images of marrow cells for the fractal dimension calculation. An efficient approach is described for the discrimination between different marrow cells with the combination of the fractal dimension.