This methodic gives new results and advices concerning to grass quality based on determination of digestibility of dry matter and fiber. Cell wall is laboratory characterized by the neutral detergent fiber (NDF) analysis. Cell content is fully digested and utilized by ruminants therefore the total grass nutritive value is mainly influenced by NDF. NDF ruminants´ utilization is the most suitable parameter of grass quality determination. The degradability and digestibility of feeds are determined using time consuming, labour and expensive in vivo, in situ and in vitro methods predominately used in research institutions. This study is intended for supplementation of grass quality information, and degradability and digestibility parameters based on chemical composition determinable in agricultural laboratories.