The insect pest, Prodiplosis longifila Gagné (Diptera: Cecidomyiidae), causes significant damage and losses in tomato crops in Manabí, Ecuador. The objective of this study was to characterize the current situation in tomato-growing areas of this province, in the cantons of Tosagua, Portoviejo, Rocafuerte, Bolivar, Sucre, Santa Ana, Jipijapa and Junin. A survey was applied to 35 producers, 15 technicians and 10 women workers, on production systems, problems and management of P. longifila, environmental and socioeconomic incidences. The analysis was deductive and inductive, and correlation, principal component analysis and hierarchical conglomerate analysis were also carried out. 100% of the producers indicated that P. longifila is the main pest, its control depends on agrochemicals and the climate has an impact on the problems it causes. Eighty-seven percent of the technicians reported severe damage to flowering and fruiting; 66% indicated that control of the pest cost up to 45% of the total cost of production. 14% abandoned the crop because of high infestation. 100% of the women did tie-up work, and 80% did pruning and harvesting. It is concluded that the main pest of tomato is P. longifila, reaching its maximum incidence and severity in flowering and fruiting and its control is exclusively with agrochemicals.