Even though grass species are one of major importance in livestock industry, the response of intergeneric hybridization of Lolium and Festuca and interspecific hybridization of Lolium m.X Lolium p. to Korean climatic condition has not been adequately documented. This reasearch was conducted to examine the growth characteristics and dry matter yield of Festulolium, cv. Felopa and C-Stamm N 66 and hybrid ryegrass, cv. Maja and Tetilelite. 1. The early growth of Italian ryegrass was better than that of hybrid ryegrass and Festulolium. The plant length and helght of Italian ryegrass were longerltaller than those of hybrid ryegrass and Festulolium, but the number of tillers of Italian ryegrass was less than that of hybrid ryegrass and Festulolium. 2. Festulolium and hybrid ryegrass were more tolerant than Italian xyegrass to winter killing, 70-80% of tillers was survived. 3. After wintering, early spring growth of hybrid ryegrass and Festulolium were better than that of Italian ryegrass. Dry matter yield of hybrid ryegrass and Festulolium were more than that of Italian ryegrass. 4. Spikes of hybrid ryegrass and Festulolium (C-Stamm N66) were more than those of Italian ryegrass. Seed yield per $m^2$ of hybrid ryegrass and Italian ryegrass were almost same, but that of Festulolium was lower.