To describe fluctuations in abundance and measure the effectiveness of the pheromone of Eoreuma loftini (Dyar), two experiments were done in a field of sugarcane (Saccharum spp. L.) at Morelos, Mexico. In the first experiment, eight traps containing E. loftini pheromone were placed randomly in the sugarcane field. The second experiment consisted of three treatments involving replacement of the sex pheromones at 30, 60, and 90 days. A population peak was observed on 21 May 2013, during the development of the crop. It was concluded that E. loftini sex pheromone was effective as an attractant for 30 days.