A blood flow simulation method for a subject-specific three-dimensional blood vessel model using a computer system, comprising: (a) receiving (S110) the subject-specific three-dimensional blood vessel model ; (b) generating (S130) a CFD model, analysis model, for blood flow analysis by applying a blood flow equation to the subject-specific three-dimensional blood vessel model ; (c) setting (S150) an initial condition at grid points of the analysis model and a boundary condition at an inlet and an outlet in the CFD model; (d) generating (S160) an LPM model , lumped parameter model, including artery parameters and microvascular bed parameters to provide an outlet boundary condition of the CFD model; and (e) performing a blood flow simulation for the CFD model by coupling the CFD model and the LPM model , characterized in that the act of (e) performing the blood flow simulation for the CFD model by coupling the CFD model and the LPM model includes: (f) performing (S170) a blood flow simulation for the CFD model under the initial condition and the boundary condition; (g) calculating (S190) a blood flow rate Qi and a total outflow blood flow rate Qtot_cfd for each outlet of the CFD model by the blood flow simulation; (h) updating (S210) the microvascular bed parameters of the LPM model by using the blood flow rate for each outlet and the total outflow blood flow rate of the CFD model; (i) updating the boundary condition of the outlet of each branch of the CFD model by using the updated LPM model ; and (j) repeatedly (S230) performing the acts of (f) to (i) until a convergence condition of the blood flow simulation for the CFD model is satisfied. (a) receiving (S110) the subject-specific three-dimensional blood vessel model ; (b) generating (S130) a CFD model, analysis model, for blood flow analysis by applying a blood flow equation to the subject-specific three-dimensional blood vessel model ; (c) setting (S150) an initial condition at grid points of the analysis model and a boundary condition at an inlet and an outlet in the CFD model; (d) generating (S160) an LPM model , lumped parameter model, including artery parameters and microvascular bed parameters to provide an outlet boundary condition of the CFD model; and (e) performing a blood flow simulation for the CFD model by coupling the CFD model and the LPM model , characterized in that the act of (e) performing the blood flow simulation for the CFD model by coupling the CFD model and the LPM model includes: (f) performing (S170) a blood flow simulation for the CFD model under the initial condition and the boundary condition; (g) calculating (S190) a blood flow rate Qi and a total outflow blood flow rate Qtot_cfd for each outlet of the CFD model by the blood flow simulation; (h) updating (S210) the microvascular bed parameters of the LPM model by using the blood flow rate for each outlet and the total outflow blood flow rate of the CFD model; (i) updating the boundary condition of the outlet of each branch of the CFD model by using the updated LPM model ; and (j) repeatedly (S230) performing the acts of (f) to (i) until a convergence condition of the blood flow simulation for the CFD model is satisfied. <EOS>