Impurity accumulation in the core dilutes the background plasma density, leading to radiative power losses and significantly degrading the confinement performance of the bulk plasma. In this work, integrated simulations are carried out using the OMFIT platform within a theoretical modeling framework to investigate electron cyclotron resonance heating (ECRH) suppression of impurity accumulation under neutral beam injection (NBI) in EAST. The influence of different impurity species ( \({}_{{3}}^{{7}} {\text{Li}}\) , \({}_{{{23}}}^{{{56}}} {\text{Fe,}}\,{}_{{{74}}}^{{{184}}} {\text{W}}\) ) on transport coefficients in EAST plasmas was analyzed, along with the effects of varying neutral beam injection power levels and the with and without of electron cyclotron heating on impurity transport coefficients. The results show that, as the atomic number and atomic mass increase, the inward neoclassical convection velocity (Vneo) becomes larger, whereas the variation in the turbulent transport coefficient is relatively small compared to that of the neoclassical transport coefficient. This leads to a more peaked peaking factor (Vtot/Dtot), resulting in a pronounced tendency for high-Z impurities with large atomic number and mass, such as \({}_{{{74}}}^{{{184}}} {\text{W}}\) to accumulate in the plasma core. For the \({}_{{{74}}}^{{{184}}} {\text{W}}\) impurity, an increase in neutral beam injection power leads to a rise in the toroidal rotation velocity (Vt), which enhances the inward neoclassical convection velocity. Consequently, the total convective velocity (Vtot) increases, resulting in more pronounced core accumulation of \({}_{{{74}}}^{{{184}}} {\text{W}}\) impurities. With the injection of 4 MW of ECRH power under 4 MW of neutral beam injection power compared to without ECRH, the total diffusion coefficient (Dtot) of the \({}_{{{74}}}^{{{184}}} {\text{W}}\) impurity is significantly enhanced, and the total convective velocity is substantially reduced, resulting in a marked decrease in the peaking factor and thereby effectively suppressing core impurity accumulation. This highlights the remarkable efficacy of ECRH in suppressing core impurity accumulation.
