Introduction. Contamination of water by heavy metals due to oil activity constitutes one of the problems of greatest concern at the local, regional and global levels, since it constitutes a danger to aquatic biota and human health. Objective. Determine the stochastic mathematical model to diagnose water and sediment quality in areas influenced by oil activity in the province of Orellana, Methodology. Data was collected through the 24 monitoring points currently active within the province, in the case of sediments, except Mini Culebra station, because they do not have data for the established years 2015-2019. The concentrations of the non-conservative compounds under study were recorded, such as: cadmium, nickel, lead and total petroleum hydrocarbons, through descriptive statistics, the river or natural channel of the first order (Napo river) and the second order (river Payamino, Coca River, Jivino River, Huamayacu River, Blanco River and Sacha River). Results. Once the mathematical model was applied in the SWAT modeling, it indicated that the TPH cover a greater range of sedimentation with a concentration of 18,704.4 to 90080 mg / ha in most micro-watersheds, the sedimentation of (Ni) ranges from 1332.68 to 1512.34 mg / ha. With the highest concentration in the micro-basins of the north and central-east zone, the concentration of (Pb) ranges from 269,948 to 323.55 mg / ha in the micro-basins of the north zone, and lastly (Cd) which is the pollutant with the lowest sedimentation presents with a concentration of 49.49 to 187.88 mg / ha, Conclusion. The data obtained exceed the carrying capacity, assuming a virtual accumulation of said pollutants analyzed in the rivers, so it is recommended to establish an environmental management plan for the control and treatment of hydrocarbon emissions caused by oil activity in the province of Orellana.