The invention provides an onion-shaped fullerene clad metal palladium core shell structure nano-particle and a preparation method thereof. The onion-shaped fullerene clad metal palladium core shell structure nano-particle is prepared as follows: 2, 4-dihydroxyl sodium benzoate-formaldehyde solution is prepared with 2, 4-dihydroxy-benzoic acid, sodium hydroxide and formaldehyde as raw materials, and is changed to sol through adjusting the pH value thereof; the sol is stood to obtain gel; then, 2, 4-dihydroxyl sodium benzoate-formaldehyde gel is put in Pd2+ contained palladium salt solution to dip for ion exchange to obtain Pd2+ carried 2, 4-dihydroxyl sodium benzoate-formaldehyde gel; and the Pd2+ carried 2, 4-dihydroxyl sodium benzoate-formaldehyde gel is grinded to gel powder for heating to 950-1500 DEG C in a mixed atmosphere of oxygen and inert gas, and is cooled in a pure inert gas atmosphere to obtain the onion-shaped fullerene clad metal palladium core shell structure nano-particle.