The invention provides a wafer grade encapsulating device of an electronic component and a manufacturing method thereof. The manufacturing method of the wafer grade encapsulating device of the electronic component comprises the following steps: a semiconductor wafer is supplied and comprises a plurality of electronic component chips, the semiconductor wafer and a bearing base plate are bonded, the back surface of the semiconductor wafer is thinned and is etched to form a groove, an insulating layer is deposited on the back surface of the semiconductor wafer in an adaptability mode, the insulating layer which is arranged at the bottom of the groove is removed, an interlaminar dielectric layer which is arranged at the bottom of the groove is removed, the partial surfaces of a pair of contact cushions are exposed, and a conducting layer is deposited on the back surface of the semiconductor wafer in an adaptability mode; after the semiconductor wafer is patterned, the semiconductor wafer and the contact cushions form an L-shaped connection, and an external conducting wire and a welding bump are formed. The invention can improve the adhesive property and the electric conductivity between the conducting wire structure and the contact cushions.