The invention provides a load-type monoatomic catalyst. The catalyst is formed by uniformly loading monodispersed metal atoms on the surface of a nano substrate material. A preparation method thereofcomprises the following steps: in an electrolyte solution containing metal salt, performing electrochemical deposition by using a three-electrode system, using a glassy carbon electrode loaded with the nano substrate material as a working electrode, using a graphite rod as a counter electrode, using a silver/silver chloride electrode as a reference electrode, performing linear volt-ampere scanning, enabling the metal atoms to be monodispersely and uniformly deposited on the nano substrate material, to obtain the load-type monoatomic catalyst. The load-type monoatomic catalyst is capable of, based on electro-deposition, constructing a monoatomic structure, through an electro-deposition method, rapidly, efficiently, and controllably depositing single atoms, and realizing deposition of positive and negative electrodes, and the obtained load-type monoatomic catalyst has important significance to a general application in the catalytic and particle physical field.