High-redshfit quasars are unique probes of the reionization epoch since they are one of the major sources of the ionizing photons and they tell us the early growth of the supermassive blackholes. In particular, luminous SDSS quasars have found that the reionization has ended at z~6 (e.g., Fan et al. 2006b) and spatially patchy reionization scenario has been suggested from their IGM measurements (e.g., Becker et al. 2015). On the other hand, considering the possible bias that the luminous quasars likely trace the most enriched large-scale structure, it is important to address typical ionizing state of the IGM using less-luminous quasars for understanding global reionization process.In this poster, I show the recent analysis of the HII region size (near-zone size) around low-luminosity quasars at z>6, which have been found by a large survey of z>6 quasars using Subaru/HSC.