In the experiment the chemical composition of rumen contents in roe deer (Capreolus capreolus) was investigated in the "Sarajevska Reka" hunting area. The investigations were done on 20 deer shot from May 2005 to January 2006. Experiment was done as random plan, with four treatments (seasons) and uneven distribution of subjects within treatments. The results of chemical analysis confirmed significant influence of season on the amount of total nitrogen and crude protein, ether extract, crude fibre, ash and ammonia nitrogen (P<0.05). Variations in pH values, NFE, calcium and phosphorus in dry matter and total ash of the rumen contents were lower and there was no significant influence of season on those parameters. The obtained results for total protein, calcium and phosphorus in the rumen contents in roe deer shot during the winter show significantly higher presence of those components than the usual recommendations for concentrate mixtures produced for the species. Although those results are not a real indication of the diet's chemical composition, they may be used as potential indicator of the quality of the diet and can be useful when formulating the additional feeding routine for winter months.