Th rice green leafhopper, Nephotettix spp. is an important insect pest of rice in Taiwan. During 1st rice crop, the population of the insect pest in central and southern parts of Taiwan used to reach more than 100 hoppers per sweep net and cause economic damage to rice plant. Besides direct damage, the hopper also act as the vector of virus diseases, such as yellow dwarf and transitory yellowing. Control of this hopper up to present is mainly depend upon insecticidal applications and more than 30 different formulated insecticides have been registered with the government for controlling this insect pest since last 10 years. In order to provide a basis for farmers to select more effective insecticides from such great amount compounds, a field reevaluation of chemicals for the rice green leafhopper control experiment was then conducted in Chiayi and Taichung districts simultaneuously in 1975 and 1978. The plot size of the experiments in two lecations were 50 m^2 with four replications and were arranged in a randomized complete block design. The insecticidal application was start while the insect population reach the level above 5 hopper per sweep net (35 cm in dia.) and the effect of insecticides were investigated 3 and 10 days after treatment for foliar application and 7 and 20 days after treatment for granules application. Results of these experiments are summarized as follows. The effect among chemicals tested on the rice green leafhopper control differed greatly. Based on data obtained from Chiayi and Taichung districts, the following chemicals namely 55% Azodrin S., 50% Tamaron EC., 40.64% Furadan FW., 27.4% Bidrin S., 20% Lannate L., 40% Kilval S., 75% Orthene SP., 50% Orthene WP., 90% Lannate WP. and 75% Furadan WP. had better effect for the control of the rice green leafhopper than the others. Dust and granular formulated compounds tested in these experiment had relative poor effect. According to the pattern of population growth of the rice green leafhopper in Taiwan in first rice crop, one to two foliar-applications in a period of booting to milky stage are need to protect rice plant from an economic damage of this insect pest.