  We report the discovery of a Compton-thick (CT) dust-obscured galaxy (DOG) at
$z$ = 0.89, WISE J082501.48+300257.2 (WISE0825+3002), observed by Nuclear
Spectroscopic Telescope Array (NuSTAR). X-ray analysis with the XCLUMPY model
revealed that hard X-ray luminosity in the rest-frame 2-10 keV band of
WISE0825+3002 is $L_{\rm X}$ (2-10 keV) = $4.2^{+2.8}_{-1.6} \times 10^{44}$
erg s$^{-1}$ while its hydrogen column density is $N_{\rm H}$ =
$1.0^{+0.8}_{-0.4} \times 10^{24}$ cm$^{-2}$, indicating that WISE0825+3002 is
a mildly CT active galactic nucleus (AGN). We performed the spectral energy
distribution (SED) fitting with CIGALE to derive its stellar mass, star
formation rate, and infrared luminosity. The estimated Eddington ratio based on
stellar mass and integration of the best-fit SED of AGN component is
$\lambda_{\rm Edd}$ = 0.70, which suggests that WISE0825+3002 harbors an
actively growing black hole behind a large amount of gas and dust. We found
that the relationship between luminosity ratio of X-ray and 6 $\mu$m, and
Eddington ratio follows an empirical relation for AGNs reported by Toba et al.
(2019a).
