Spodoptera exigua is reported infesting asparagus for the first time in Taiwan. At room temperature, the noctuid had 11 generations a year, generations being completed in 21.28-79.13 days. The number of eggs laid per female averaged about 300, there were 5 larval instars, and pupation took place in the soil. The noctuid was found throughout the asparagus-growing area of Taiwan and infested > 30 host plants. Larvae were killed by a nuclear polyhedrosis virus in January-April and July-August, and the fungal pathogen Beauveria bassiana infected larvae readily in the laboratory and field. Snellenius manilae and an ichneumonid were common larval parasitoids. The use of light traps and pheromone traps was investigated. Against larvae, 3% Thuricide WP [Bacillus thuringiensis], 40.8% Dursban EC [chlorpyrifos], 90% Lannate WP [methomyl] and 20% Sumicidin WP [fenvalerate] gave good results. Although the asparagus aphid Brachycolus asparagi [Brachycorynella asparagil has not been found in Taiwan, its ecology was studied there. none