A field experiment was carried out to determine the effects of nitrogen(N) fertilization levels(0, 30, 60, 90 and 120 kg/ha) in early spring on the growth, dry matter(DM) yield, seasonal distribution of production and nutritive value of grasses. Additional N after the first, second and third harvest were applied as 60, 60 and 30 kg/ha, equally in 1989. Grass growth and DM yield were significantly increased(p<O. 05) with increasing of N in early spring, and 90 kg of N was very benefitial on annual grass production. Also more than 60 kg of N application showed good seasonal distribution of annual production. With increasing level of N, crude protein(CP) content and CP yield were significantly increased(p<O. 051, the contents of NDF, ADF and hemicellulose were tended to increase, and DM digestibility was tended to decrease. However, $NO_3$-N concentration was not affected by N level of early spring. It is suggested that, therefore, N application in early spring is essential, and 60 to 90 kg/ha of N application may be desirable in early spring.