Provided are a mating disruptant having an improved mating disruption effect against pest insects. Specifically, provided is a mating disruptant for the control of pest insects whose natural sex pheromone composition is substantially free of an alcohol and comprises one or more acetates, the disruptant comprising the one or more acetates and an alcohol or alcohols which can be derived from the one or more acetate, wherein an amount of each of the alcohol or alcohols is from 0.5 to 10% by weight relative to an amount of each deriving acetate and a mating disruption method using the mating disruptant. The alcohol which can be derived from the acetate is an alcohol obtainable by hydrolysis of the acetate and means an alcohol component of the ester derived from an acid and the alcohol.