This work reveals a schematic strategy to massively fabricate a series of OH-riched copper oxides (CuO-OH), which could be used as highly efficient chemo catalysts for water oxidation reaction (WOR). The results indicate that the as-prepared CuO-OH exhibited excellent catalytic activity (2,900 μmol·h-1·g-1) toward water oxidation, far higher than the pure CuO formed through calcination. According to the radical capture results and the DRIFTS, XRD, and Raman spectra data, sulfate radicals were the main active species. Subsequent data of BET, HR-TEM, and FT-IR spectra reveal that the CuO-OH could activate persulfate ions in the dark to produce sulfate radicals efficiently at room temperature and promote the sulfate radicals to carry out immediately to hydroxide-mediated deprotonation steps in WOR. Based on the results above, a mechanism is proposed.