This study is to examine the colorfastness of leathers which has been tested for concentration of dyestuff and method of dyeing. This study particularly attempts to solve some problems of colorfastness in wearing and treating leather goods. The finding of this study can summarized as follows: 1. In dyeing garment leathers classified by concentration, the colorfastness to light improves as concentration increases. 2. As the result the more concentration increases, the more the colorfastness to rubbing declines. 3. In colorfastness to dry cleaning, the grade of color fading has been to be high but that of staining to be bad as concentration increases. 4. In assessing change in colorfastness, grades to light and rubbing after coating have been found to be better than that before coating. 5. In colorfastness to dry cleaning after coating, both grades of color fading and staining have been found to be bad.