본 연구는 국내 개발 이탈리안 라이그라스(IRG)와 청보리 품종의 생산성과 사료가치를 비교분석하여 영농현장에 필요한 기술정보를 제공하고자 국립축산과학원 수원 시험포장에서 2009년 9월부터 '10년 6월까지 수행하였다. 처리내용은 IRG 2품종(조생종 Kowinearly, 중생종 Kowinmaster), 청보리 5품종(영양, 우호, 유연, 다미, 유호) 및 혼파구(Kowinearly + 유연, Kowinmaster + 유연) 등 9처리였다. IRG의 출수기는 Kowin early 5월 14일, Kowinmaster 5월 18일이었다. 5월 22일 조사한 청보리의 숙기는 영양과 우호는 유숙후기, 다미는 호숙초기, 유연과 유호는 호숙초 중기로 품종간 약간의 차이가 있었다. IRG에서 도복이 다소 있었으나 혼파구에서는 관찰되지 않았고, 혼파구에서 IRG의 초장은 117~118 cm로 IRG나 청보리 단파구에 비해 길었다. 수확 시 건물률은 20.7~25.4%였으며, 혼파구에서 시기별로 조사한 IRG의 식생비율은 평균 43.1%였다. 청보리의 이삭비율은 성숙이 진행될수록 높아지는 경향으로 유숙후기, 호숙기, 황숙기, 완숙기에서 각각 35.7%, 44.1%, 54.8%, 57.2%였으며, 품종별로는 영양과 우호에서 다소 높은 경향이었다. 조단백질 함량은 IRG에서 9.0~10.0%로 높은 경향이었으며 청보리는 7.0~8.5%, 혼파구는 7.3~9.1%였고, NDF와 ADF 함량은 청보리구에서 낮은 경향이었다. 건물 소화율은 Kowinearly 64.4%, Kowinmaster 64.1%, Kowinmaster + 유연 혼파구는 64.5%였으며, 청보리는 60.2 (유호)~66.4% (우호) 범위로 우호에서 높은 경향이었다. 건물수량, 조단백질 수량, 가소화 건물수량은 Kowinmaster + 유연 혼파구에서 ha당 각각 11,508 kg, 1,046 kg, 7,422 kg으로 가장 많았으며(p<0.05), IRG와 청보리 품종별 생산성 차이는 크지 않아 지역 특성과 재배 목적에 맞는 초종 및 품종선택과 함께 IRG (Kowinmaster) + 청보리 혼파이용이 권장되었다. This study was carried out to determine the forage production and quality of Italian ryegrass (IRG) and forage barley developed by Korea in Suwon, 2009~'10. The nine treatments were two IRG varieties (Kowinearly with early maturity and Kowinmaster with medium maturity), five barley varieties (Youngyang, Wooho, Yuyeon, Dami and Youho), and two mixtures (Kowinearly + Yuyeon and Kowinmaster + Yuyeon). The heading dates of Kowinearly and Kowinmaster were 14 May and 18 May, respectively. The growth stage of barley investigated at 22 May were late milk in Youngyang and Wooho, early dough in Dami and early to medium dough in Yuyeon and Youho. Plant length of IRG in IRG + barley mixtures was 117~118 cm, which was longer than those of IRG monoculture of 98~101 cm, and no lodging was found in mixtures. The dry matter (DM) percentage at harvest was 20.7~25.4% in all treatments. The botanical composition of IRG in mixtures was 43.1%. The percentage of spike per barley plant was become high according to progressed maturity, as a 35.7%, 44.1%, 54.8% and 57.2% in late milk, dough, yellowish and full ripeness stage, respectively, and the spike percentages of Youngyang and Wooho were tends to high. The crude protein (CP) content of IRG as 9.0~10.0% was higher than that of barley (7.0~8.5%), and the contents of NDF and ADF of barley were lower than those of IRG, and in vitro DM digestibility were 64.4% in Kowinearly, 64.1% in Kowinmaster, 64.5% in mixture, and 60.2% (Youho) to 66.4% (Wooho) in barley. The yields of DM, CP and in vitro digestible DM were high in Kowinmaster+barley mixture as a 11,508 kg, 1,046 kg and 7,422 kg per ha, respectively (p<0.05). However, no significant differences in forage yield were observed among cultivar of IRG, and barley, although Wooho was tends to high in digestibility and forage yield among five barley varieties. In conclusion, the mixture cultivation of IRG Kowinmaster + forage barley was recommended, because of preventing of IRG lodging, higher plant length of IRG, increasing of forage yield, and stable production. Selection of suitable winter forage species and variety for district, climate environment, and utilization type of farm was also important.