The restoration of macroalgae from urchin barrens relies upon the components of macroalgal seed bank. However, the bank was less understood due to invisibility of the microscopic forms of macroalgae. In the present study, we detected components of the banks in four different depth (1, 2, 5 and 7 m in depth) of urchin barren grounds based-on meta-DNA barcoding using next-generating sequencing (NGS) system. In addition, the components of the bank were also compared with kelp or soft coral dominant bed to understand the variation among different ecological phases. In the rarefied data, totally fifty-four OTUs were obtained from collected 30 cobbles, and thirty-one to sixty (43.7 ? 9.9, mean ? SD) OTUs were detected in each site. The rarefied number of macroalgal OTUs gradually increased onward to the deeper site, which was three times larger in the depth of 7 m (UB7) than 1 m. Similarly, the Shannon-Weiner diversity index was the highest in UB7. The number of OTUs and diversity in the bank in UB7 were equivalent to adjacent kelp bed. The released spores and macroalgal fragments are generally sink down from shallow to deeper waters thereby the variation by the depth detected. The findings would contribute to effective restorations from urchin barrens.