In this article, Co 3 O 4 with different morphologies direct growth on nickel foam is successfully synthesized via a simple hydrothermal method by changing the volume ratio between ethanol and water. The morphology and structure of the as-prepared samples are examined by Scanning electron microscopy, Transmission electron microscopy, X-ray diffractometer and Fourier transform infrared spectroscopy. The electrochemical performances of the Co 3 O 4 electrodes are investigated as pseudocapacitor material by cyclic voltammetry and galvanostatic charge/discharge test in 3 mol L -1 KOH solution. Results show that the solvent composition plays an important role not only in the morphology but also in the capacitance. Co 3 O 4 with a honeycomb structure obtained from the volume ratio of C 2 H 5 OH/H 2 O=1 exhibits the highest capacitive performance, 2509.4 F g -1 at 1 A g -1 and 1754 F g -1 at 10 A g -1 , which is much larger than that prepared in the pure water and pure ethanol solvent. The electrode also has a satisfactory cycling performance with capacity retention of 74 % after 1000 cycles at 10 A g -1 .The enhanced electrochemical performances are ascribed to the honeycomb nanostructure allowing facile electrolyte to flow which fastens electrochemical reaction kinetics. These findings may open up the opportunity on optimizing the hydrothermal synthesis conditions to control the morphology and performance of the products.