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EAST tokamak has been equipped with upper tungsten divertor since 2014. The tungsten accumulation has been often observed in NBI-heated H-mode discharges suggesting deleterious tungsten confinement in the plasma core. It causes not only H-L back transition but also plasma disruption in several discharges. Suppression of the tungsten accumulation is therefore the most important issue in EAST to achieve a long pulse H-mode discharge. In order to study the tungsten behavior in the long pulse discharge, tungsten spectra have been measured at 20–140 Å. The tungsten density, n_w, is evaluated from the intensity of tungsten unresolved transition array (W-UTA) in a wavelength range of 45–70 Å which is composed of several ionization stages of tungsten, e.g. W²⁷⁺-W⁴⁵⁺ at T_e0∼2.5 keV). It is found that the tungsten accumulation can be suppressed when the 4.6 GHz LHW with P_LHW∼0.8 MW is …