In this study effect of blood perfusion (BP) on diffusion of magnetic nanoparticles (MNPs) inside a biological tissue during magnetic fluid hyperthermia (MFH) has been simulated using the lattice Boltzmann model (LBM). To validate the numerical results, diffusion in infinite one and two dimensional domains has been compared with the analytical solution. Agreement was excellent. Also effect of the BP on diffusion of a water based nanofluid containing magnetite MNPs (ferrofluid) in the tissue has been studied.