During the years 2008-2010 the study in two farms ensilaging meadow sward in big bales was carried out. The aim of study was to asses the influence of dry matter content in ensilaged material on quality and nutritive value of obtained silages. Appropriate concentration of dry matter in ensilaged material was important factor influencing the fermentation process and final quality of silage. Obtaining the optimal level of dry matter in ensilaged material depended on many factors, including among others weather conditions during the pre-wilting process, length of pre-wilting process and the use of technological operations preceding the harvest of pre-wilted plant material. Ensilage of pre-wilted material before harvest caused the linear increase of pH value of silage with simultaneous decrease in the ammonia concentration. With dry matter content increase to level of 45-50% the decrease in the concentration of volatile fatty acids was observed. Longer drying of plant material above 55% resulted in an increase of concentration of these acids. The optimum dry matter content in ensilaged plant material to obtain the highest proportion of lactic acid in grass silage was 25-35%. Stronger pre-wilting did not cause a further increase in the contribution of lactic acid in sum of total fatty acids and had not any positive impact on intake, digestibility and nutritive value.