アブストラクト：
"Based on newly released Subaru/Hyper Suprime-Cam (HSC) photometry data, we select ~3,500 z~4 faint QSOs at m_{i}<24 and ~10,000 z~4 LBGs at m_{i}<24.5 in WIDE survey region. We estimate the bias factor for QSO and LBG by checking their two point angular auto-correlation function and cross-correlation function respectively. The preliminary result indicates that, as similar with more luminous SDSS QSOs in the same redshift range, faint HSC QSOs at z~4 also have strong auto-correlation which suggests the QSO host dark matter halo (DMH) mass is as massive as ~10^{13} solar mass (under further check). Meanwhile, the cross-correlation between QSO and LBG is not so strong which doesn't support such large dark matter halo mass. This discrepancy may give a hint on the origin of the super massive black hole in DMHs and triggering mechanism for QSO."