A multiple input power distribution shelf and a bus bar assembly thereof are provided. The power distribution shelf is installed in the server rack and comprises plural power supply units. The bus bar assembly comprises a first linking bus bar, a second linking bus bar, an insulation member and plural power connectors. The first linking bus bar comprises a first main bar, plural first bending parts and at least one first output part. The second linking bus bar comprises a second main bar, plural second bending parts and at least one second output part. The insulation member is disposed between the first main bar and the second main bar for insulation. The power connectors are mounted on the bending parts and connect with the power supply units. The first output part and the second output part are electrically connected with a rack bus bar of the server rack.