Metal complex dyes are usually used to dye amide fiber such as wool, silk and nylon to achieve high concentrated color and excellent color fastness. However, metal complex dyes that contain various heavy metal components cause not only serious environmental problem but also human health. In this study the ordinary 1:2 metal acid dyes and the modified 1:2 metal dyes, which are environmental friendly, are compared and analyzed in existing dyes investigated the trends in the evaluation system of their harmfulness, containing heavy metals and examined exhaustion rates and dyeing characteristics.