Experiments were conducted in 4 fields in Taichung Prefecture of Taiwan to evaluate the integrated effect of sex pheromone and insecticide in the control of sweetpotato weevil (SPW), Cylas formicarius Fabricius. The results show that the use of pheromone-baited traps placed at a density of 4 traps/0.1 ha reduced 65% of storage root damage caused by SPW compared with that of the untreated control. Use of pheromone-baited traps in combination with preplant application of Dursban at 2.25 kg a.i./ha reduced storage root damage by 75%. These effects are comparable to that from 2 applications of Dursban, one before planting and another at the time of earthing-up. Correlation analysis revealed that the best criterion for evaluating the loss of sweetpotatoes caused by SPW was the number of damaged storage roots.