This experiment was canied out to determine the effects of 3cn1, 6cm, and lOcm of cutting height at harvest on the grass growth, dry matter(DM) yield, and weeds development in reed canarygrass(Phu1uris umndinacea L.) pasttire. The cultivars of reed canarygrass used in this study were Palaton. Veuture and Frontier(contro1). and the grass was harvested four times at soiling stage in 1992. The plant height at first harvest was 84, 96 and 94cm in Palaton, Venture and Frontier, respectively. The average regrowth height was same as 59cm in three cultivars. However, the regrowth height by cutting height was 61 -65cm in 6 and IOcm, and 51 -53cm in 3cm of low cutting height. Annual DM yield was not different in three cultivars of Palaton(l2.58lkg), Venture(l2,752kg), and Frontier (12,243kgIha). The yield at first harvmt wa5 significantly high in 3cm of height, however, the forage yields at second, third and fourth harvest were greatly high in 6cm of stubble height(P<0.05). Total yields by 3, 6 and lOcm of cutting height were 12.306. 14,094 and 11,342kg in Palaton, 12,794, 14,155 and 11,307kg in Venture, and 12,258, 12,940, and 11.535kglhg in Frontier, respectively. The highest yield was achieved in 6cm of stubble heigth(P<0.05). Daily DM production during grass regrowth was not affected by cultivars, and the best regrowth was observed by 6cm of cutting height. Development of weeds was high in 3cm of low stubble height, regradless of cultivars. The contents of crude protein, neutral detergent fiber, acid detergent fiber, and hemicellulose were not affected by cultivar and cutting height. In conclusion, it is suggested that the 6cm of cutting height is the most effective for grass regrowth, forage production, and weed control in reed canarygrass pasture. regradless of cultivm of Palaton, Venture and Frontier.