The tropical root weevil, Diaprepes abbreviatus (L.), is a major pest of many plants of economic importance, including citrus and ornamentals. It was accidentally introduced from the Caribbean into Florida in the 1960s and its range within the United States now includes Texas and California. No safe and effective control method is available for this species. Studies of the reproductive behavior of field populations may aid the development of effective control strategies and inform laboratory experimental design. We examined mating patterns of individually-marked D. abbreviatus in a plant nursery in Florida over 5 d. Matings occurred throughout the day but tended to peak during the middle of the day. Mating duration ranged from less than 3 h to over 9 h. Most males and females mated repeatedly, sometimes with the same partner multiple times. Both same-sex and extra-pair mountings occurred at low frequencies. In a follow-up study conducted in captivity, we found no short-term direct benefits of multiple mating to females but female fertility decreased dramatically by 2 weeks after mating if females were not allowed to re-mate. Thus, female D. abbreviatus may re-mate, in part, to replenish sperm stores. Our results suggest that the sterile insect technique would not be effective but support previous conclusions that pheromones may be effective attractants in this species because both females and males mate multiple times in the field.