The lack of information on the erosivity of rain in the Sierra Norte de Puebla has prevented an objective assessment of its contribution to the erosion process. The aim of this work was to determine the erosive potential and temporal variability of precipitation in the San Marcos river sub-basin, based on different indices that measure the degree of aggression of precipitation, and to establish relationships between them. Ten year rainfall records of seven meteorological stations were used. The Annual Fournier Index (APIs), Fournier Modified Index (FMI), Precipitation Concentration (ICP) and Total Erosivity (TER) were calculated. The study concludes that the risks of erosion are greater in the area of influence of the climate stations of Xicotepec, Venustiano Carranza and Progreso, located at altitudes between 1279 and 886 msnm. Precipitation according to the ICP is concentrated in a moderate seasonal manner from July to October, and the EIT shows that precipitation is highly erosive. The results would inform the development of an agro-ecological soil conservation strategy based on the climate aggression presented in the study area.