The paper presents fractional composition and optical properties of the soil organic matter (SOM) developed on afforested dumping ground of the sulphur strip mine in Piaseczno near Tarnobrzeg (southern Poland). Research was designed for different soil−substrates and trees species. Soil−substrate type has the major impact on SOM characteristics at current stage of soil development. Black alder characterized with the strongest influence on SOM quality among species introduced on the dumping ground.