The invention relates to a chip packaging structure and a forming method thereof. The packaging structure comprises a chip, a packaging body, a first patterned protection layer, a metal layer, a second patterned protection layer, a plurality of patterned UBM layers and a plurality of conductive assemblies, wherein a plurality of soldering pads and adhesion layers are respectively arranged on an active surface and a back surface of the chip; the packaging body is annularly covered on four surfaces of the chip so as to expose the soldering pads of the chip out and is provided with a plurality of through holes; the first patterned protection layer is formed on the partial surface of the packaging body and the active surface of the partial chip and exposes the soldering pads and the through holes out; the metal layer is covered on the partial surface of the first patterned protection layer, and is electrically connected with the soldering pads and filled in the through holes; the second patterned protection layer is covered on the first patterned protection layer and a part of metal layer and exposes the partial surface of the metal layer out; the patterned UBM layers are formed on the partial surface of the exposed metal layer and the partial surface of the second patterned protection layer and are electrically connected with the metal layer; and the conductive assemblies are formed on the patterned UBM layers and electrically connected with the metal layer through the patterned UBM layers.