A method and system for visualization of a direction of a fluid flow in heterogeneous porous medium in hydrocarbon reservoirs based on the streamlines. The method allows for constructing the detailed and accurate model of a direction and a volume of the fluids being transferred between the wells and can be used for analysis of waterflooding and hydrodynamic connectivity between the wells used in oil and gas reservoirs with a large number of wells. The visualization method can be used both for analysis of instantaneous fluid flows at the current calculation step of hydrodynamic simulator and for analysis of fluid flows accumulated over several calculation steps.