Electrocatalysis plays a critical role to tackle the global challenges of energy and environment. Introduction of new concept, theory, method and paradigm has spurred its prosperous development; and as an indicator, the scientific publications have been doubled in last five years. Major efforts have been devoted to the material research to improve the electrocatalytic activity; however, the 'structure-activity' relationship, which is the ultimate target of electrocatalysis as for its scientific significance, is not well understood yet. The concept of precise electrocatalysis affords the possibility to achieve this goal, which includes but is not limited to: i) molecular/cluster electrocatalyst with well-defined composition/structure, ii) precise synthesis strategy for heterogeneous electrocatalyst, iii) identification of reactive species, the active sites, intermediates and their dynamic evolution in reaction at atomic/molecular level.