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Introduction: The forests are home to more than half of the planet's species, despite of their biodiversity, they are the ecosystems most threatened mainly by anthropic activities, but their complexity in relation to altitude has information gaps despite of the values it represents. Objective: Describe the structure and diversity of trees on an altitudinal gradient. Methods: In five altitudinal strata (EA) 21 sampling plots (UM) of 20 x 50 m were established: six in EA1, five in EA2, four in EA3, three in EA4 and 5. The structure was characterized by the categories diametric and height, and the importance value indexes (IVI) and forestry (IVF). Diversity was analyzed with the Shannon-Wiener (H´) and Simpson (S) indices, while the floristic similarity with the Sørensen coefficient (IS). Results: It was registered 209 tree species, eight are listed in the Official Mexican Standard-059-Secretariat of the Environment and Natural Resources-2010 (NOM-059-SEMARNAT-2019) as vulnerable species. The species with the highest IVI and IVF were Haematoxylum campechianum and Manilkara zapota in EA1; Rinorea guatemalensis and Pouteria reticulata in EA2; M. zapota and Brosimum alicastrum at EA3; Guatteria anomala and Pseudolmedia spuria in EA4; and Terminalia amazonia and Pouteria durlandii at EA5. In the five EAs, three ranges of height and six of diameter were identified, the largest number of individuals was found in the first diametric range. Species diversity was lower at higher altitudes. In EA 2 and 3 the greatest similarity was presented (IS= 58.7 %). Conclusion: The structure and diversity of the tree species present greater changes in wider altitude ranges, related to the environmental need of each species. It was registered 209 species, eight are listed in the Official Mexican Standard-059-SEMARNAT-2010 as vulnerable species. The species with the highest importance value index and forest importance value index were Haematoxylum campechianum L., Manilkara zapota (L.) Royen in the altitudinal strip 1; Rinorea guatemalensis (S. Watson) Bartlett, Pouteria reticulata (Engl.) Eyma in the altitudinal strip 2; M. zapota, Brosimun alicastrum Sw in the strip 3; Guatteria anomala R.E. Fr, Pseudolmedia spuria (Sw.) Griseb in strip 4; y finally Terminalia amazonia (J. F. Gmel.) Ecell, P. durlandii in altitudinal strip 5. In the five strata, three height ranges and diametric categories were identified. The largest number of individual was registered in the first diametric category (< 10 cm). The species diversity of the species was lower alt higher altitude. In stripes 2 and 3 the greatest similarity was present (IS = 58.7%). Conclusion The diversity of species was influenced by altitude. In some places population of almost the same species are constituted as an adaptation to the effect of height Key Words: tropics, Perennifolia, basal area, wealth, jungle. Introducción: Las selvas albergan más de la mitad de las especies del planeta, a pesar de la biodiversidad que poseen son los ambientes más amenazados, principalmente por actividades antrópicas, y su complejidad con relación a la altitud alberga vacíos de información a pesar de los valores que representa. Objetivo: Describir la estructura y diversidad de árboles en un gradiente altitudinal. Métodos: En cinco estratos altitudinales (EA) se establecieron 21 unidades de muestreo (UM) de 20 x 50 m: seis en el EA1, cinco en EA2, cuatro en EA3, tres en EA4 y 5. La estructura se caracterizó mediante las categorías diamétricas y de altura, y de los índices de valor de importancia (IVI) y forestal (IVF). La diversidad se analizó con los índices de Shannon-Wiener (H´) y Simpson (S), mientras la semejanza florística con el coeficiente de Sørensen (IS). Resultados: Se registraron 209 especies, ocho registradas en la Norma Oficial Mexicana-059-Secretaría de Medio Ambiente y Recursos Naturales-2010 (NOM-059-SEMARNAT-2019). Las especies con los mayores IVI e IVF fueron: Haematoxylum campechianum y Manilkara zapota en EA1; Rinorea guatemalensis y Pouteria reticulata en EA2; M. zapota y Brosimum alicastrum en EA3; Guatteria anomala y Pseudolmedia spuria en EA4; y Terminalia amazonia y Pouteria durlandii en EA5. En los cinco EA se identificaron tres rangos de altura y seis de diámetro, el mayor número de individuos se encontró en la primera categoria diamétrica. La diversidad de las especies fue menor a mayor altitud. En los EA 2 y 3 se presentó la mayor semejanza (IS = 58.7 %). Conclusión: La estructura y diversidad de las especies arbóreas, presentan mayores cambios en intervalos altitudinales más amplios, relacionados con la necesidad ambiental de cada especie.