Physiological characteristics should be defined for better assessment of plant growth and development. Such characteristics play a significant role in finding out optimum intervention time. Vetch is commonly used in animal feeding. Therefore, it is quite significant to work on vetch yield and quality. Vetch constitutes about 10% of feed crop production of Turkey. Therefore, vetch cultivars and lines were used and physiological characteristics of Narbon vetch (Vicia norbonensis L.) plants were determined. Leaf area index, leaf area ratio, relative leaf growth ratio, relative growth ratio, net assimilation ratio and plant growth ratio were determined.