Using the one-atom theory（OA）, the atomic states of Ru-electrocatalyst with hcp structure was determined as Kr（4dn）^3.78（4dc）^2.22（5Sc）^1.77（5Sf）^0.23. The potential curve, elasticity and the temperature dependence of linear thermal expansion coefficient and bulk modulus of hcp-Ru were calculated quantitatively. The atomic states of this metal with fcc and bcc structure and liquid state were also studied. According to its atomic states, the relationship between the atomic states and catalytic performance was explained qualitatively and these supplied Ru-metal and electrocatalyst with complete data for optimum designation in accordance with metal material systematic sicence.