The banana skipper,Erionota torusEvans, was discovered for the first time as a new banana pest in Taiwan on September 1986. Monthly surveys indicated that within a year this hesperiid is well established and widely distributed in major banana‐growing areas of southern Taiwan. The infestation rates were higher in spring and autumn‐winter seasons, ranging from less than 5% to higher than 20% in different areas. A damage pattern of 1.11 (average) infested leaves per infested plant and 1.17 (average) rolls per infested leaf was found. With highly significant linear correlations between banana plant and leaf infestation rates versus skipper larvae and pupae counts in the field, a rapid and simple measurement to determine banana plant infestation rate (percentage) will be adapted for future studies on the population fluctuation and extent of damage.