The present invention provides a metal interconnection structure and a manufacturing method thereof, wherein the manufacturing method comprises the following steps: firstly providing a semiconductor substrate with a target electric connection area; afterwards forming a patterned amorphous carbon layer or photoresist layer, wherein the patterned amorphous carbon layer or photoresist layer comprises a first layer and a second layer which are vertically connected; afterwards forming a metal layer on the semiconductor substrate; then etching the metal layer, keeping the metal layer of the side wall of the patterned amorphous carbon layer or photoresist layer, eliminating the metal layer of other areas, wherein the kept metal layer corresponds with the target electric connection area; then eliminating the patterned amorphous carbon layer or photoresist layer for forming metal interconnection wire patterns; and finally filling a dielectric material between the metal interconnection wire patterns for forming the metal interconnection structure. According to the technical solution of the invention, the metal interconnection structure with small parasitic capacitance and high conductivity is provided.