In the electroplating and water treatment fields, as the demand and expectation on an electrode with high productivity and high efficiency are getting increased, various electrodes(DSE) with higher reactivity and durability are being developed. This study is intended to analyze the characteristics of the produced electrodes and to establish the optimum manufacturing conditions for electrode being used that we mentioned. For improving the durability, the changes of reactivity and corrosion resistance are observed as adding Tantalum and/or another components (hereafter stated as “α”) and surface treatment of substrate(Ti). As a result, increasing the amount of Iridium, the reactivity of electrode increased, and increasing amount of Tantalum, the durability of electrode increased. And thus, it is found out that Iridium and Tantalum have the opposite role each on the electrode’s reactivity and durability. And adding α and surface treatment substrate, an electrode with excellent reactivity and durability and low oxygen evolution can be manufactured. In the water treatment field like sterilizing in a swimming pool and power-plant cooling water, the high efficiency of sodium-hypochlorite generation is surely guaranteed.