Recent developments in technology and soil science have drawn particular attention to peatlands and their behaviour, properties and utilisation. Further, characteristics of peat are very important in evaluating it as a plant growth medium. The objective of this study was to characterise a number of samples collected from different depths of five different profiles of Yenicaga peat (carex) by measuring the organic carbon, total nitrogen, and extinction values (Er) of their humic acid fractions (HAs) in comparison with decomposition degrees. Peat samples having a high decomposition degree were near to the Er45 axis in the ordinate and had high Er67 values, whereas peats with low decomposition degree were far from the Er45 axis and had low Er67 values.