The preparation of superconducting YBa₂Cu₃O_2y through sol-gel method was performed using an acetate aqueous solution. Conditions of gelation and conversion of gel to YBa₂Cu₃O_2y ceramics were investigated, applying thermal analysis, infrared absorption spectroscopy and X-ray diffraction techniques. Transparent gel was obtained from the acetate solution with cation mole ratio of Y:Ba:Cu=1:2:3 by adjusting the initial pH of the solution. Formation of Cu metal, Cu₂O and BaCO₃ below 400°C was found to occur during heat treatment of the gel. Above 600°C the heated sample turned into a mixture of Y₂O₃, BaCO₃ and CuO, which finally transformed into the single phase of YBa₂Cu₃O_2y at 910°C. The resultant material showed good high T_c superconductivity.