Maize (Zea mays L.) is an important crop for personal consumption and marketing, but production can be affected by the fall armyworm, Spodoptera frugiperda (J.E. Smith). The objectives of the research were to determine species of parasitoids associated with the fall armyworm at three localities in Tamaulipas and to evaluate natural parasitism and determine the species most frequent at the sampling sites. S. frugiperda larvae were collected at the municipalities of Güémez, Llera, and Victoria, and its development was continued until adult parasitoids or S. frugiperda emerged. The effect of collection date and natural parasitism in S. frugiperda was evaluated with two logistic regressions of binary response. Probability of occurrence of the species was estimated with a multinomial logistic regression. Seven species of parasitoids were obtained. Most parasitism was at Victoria and Güémez in March, with least at Güémez in September. According to model estimation, most parasitoid activity would be expected at Victoria in March; in addition to minimal total parasitism of 21.8%. Most parasitism was 11.4% by Chelonus (Chelonus) sonorensis Cresson, followed by Campoletis sonorensis Cameron, with 6.1%. Ch. sonorensis was most probable at Güémez, followed by Victoria and Llera (0.53, 0.37, and 0.34, respectively). C. sonorensis was the second most important parasitoid at Güémez and Victoria (0.31 and 0.27) while most Meteorus arizonensis Muesebeck (0.29) was at Llera. Ch. sonorensis was the most suitable species as a biological control agent against S. frugiperda at the sampled sites.