Some attempts were made to investigate the biological characterisitcs of the green rice leafhopper(GLH) , Nepthotettix cincticeps Uhler in terms of nymphal development, emergence ratio. preovipositional period, growth index, adult longevity and fecundity fed on rice cultivar, Chucheongbyeo with no resistance gene and water foxtail, Alpecurus aequalis Sobol. var. amurensis Ohwi at 20 and $25^{circ}C$ with a 16L;8D photoperiod. Development period of nymph on rice cultivar and water foxtail at $25^{circ}C$ was shorter than that at 2$0^{circ}C$ by twofold. The nymphal period of female was about one day longer than that of male. The mean emergence ratio of female and male on rice cultivar and water foxtail was 40.0, 76.7, 38.3, 73.3% at 20 and $25^{circ}C$, respectively. Preovipositional period on rice cultivar and water foxtail at $25^{circ}C$ was shorter that at 2$0^{circ}C$ by twofold. Growth index on rice cultivar adn water foxtail at $25^{circ}C$was higher than that at 2$0^{circ}C$ by fourfold. Under the 20 and $25^{circ}C$ condition, the longevity of female and male was longer on water foxtail than on rice cultivar, but the fecundity of GLH was higher on rice cultivar than on water foxtail. In conculsion, water foxtail seems to be adequate for spring host of GLH.