Complementary metal oxide semiconductor (CMOS) technology with high transconductance and signal gain is mandatory for practicable digital/analog logic electronics. However, high performance all-oxide CMOS logics are scarcely reported in the literature; specifically, not at all for solution-processed/printed transistors. As a major step toward solution-processed all-oxide electronics, here it is shown that using a highly efficient electrolyte-gating approach one can obtain printed and low-voltage operated oxide CMOS logics with high signal gain (≈21 at a supply voltage of only 1.5 V) and low static power dissipation. An electrolyte-gating approach offers decisive advantage to solution-processed oxide field-effect transistors. Printed oxide semiconductors usually suffer from large surface/interface roughness, resulting mediocre electrical performance compared to sputtered thin films. However, an electrolyte as the gate insulator can provide conformal interface to irregular semiconductor surfaces, resolving the issue; consequently, all solution-processed oxide logics with high signal gain become feasible. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.