Ti/IrO2-Ta2O5　electrodes　were　prepared　by　a　low　thermal　decomposition　method.　The　influence　of　Ta　contents　on　the　microstructure　and　capacitive　performance　of　the　Ti/IrO2-Ta2O5　electrodes　was　investigated　by　XRD,　cyclic　voltammetry,　electrochemical　impedance　spectroscopy　and　galvanostatic　charge-discharge　tests.　The　results　show　that　Ta2O5　can　inhibit　crystallization　of　the　IrO2.　With　increasing　Ta　content,　the　crystallization　degree　decreases.　When　the　content　of　Ta　is　60　mol%,　the　electrode　with　a　content　of　6.4%　crystalline　structure　has　a　superior　capacitive　performance　of　239.2　g/F,　which　is　considerably　higher　than　that　of　IrO2　electrode　(54.1　g/F).