A semiconductor package and a fabrication method thereof are disclosed. The fabrication method includes the steps of providing a semiconductor chip having an active surface and a non-active surface opposing to the active surface, roughening a peripheral portion of the non-active surface so as to divide the non-active surface into the peripheral portion formed with a roughened structure and a non-roughened central portion, mounting the semiconductor chip on a chip carrier via a plurality of solder bumps formed on the active surface, forming an encapsulant on the chip carrier to encapsulate the semiconductor chip. The roughened structure formed on the peripheral portion of the non-active surface of the semiconductor chip can reinforce the bonding between the semiconductor chip and the encapsulant, and the non-roughened central portion of the non-active surface of the semiconductor chip can maintain the structural strength of the semiconductor chip.