Using the Suprime-Cam on the Subaru telescope, we carried out deep multi band ( V, R, I, z') imaging for the host galaxy of GRB980329, which is one of well studied “optically dark” gamma-ray bursts. The host galaxy was detected clearly in all bands. Combining these measurements with published near-infrared data, we determined the photometric redshift of the galaxy as z = 3.56 (3.21-3.79 at 90range). The implied V-band extinction is rather low, typically ˜ 1 mag. At z = 3.56, the isotropic 40-700keV total energy of GRB980329 is calculated as (2.1±0.4)×1054erg. Assuming that this GRB was emitted by a pair of jets with a total energy of 1051ergs, their opening angle is calculated as &thetas;j = 2.1. The present results disfavor the high-redshift hypothesis and the high extinction scenario of optically dark bursts.
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