The invention discloses a busbar preparation method and a capacitor busbar prepared by the busbar preparation method. The preparation method is used for preparing a busbar with a connection terminal perpendicular to a substrate and located in the middle part of the substrate. The preparation method includes the following steps: bending a copper plate into a wiring part and a connecting part, wherein the wiring part is the same as the part of the connection terminal perpendicular to the substrate, and the connecting part is perpendicular to the wiring part; setting at least one accommodating groove matched with the connecting part on the substrate; and welding the connecting part and the accommodating groove into a whole at the connection position through laser welding. The invention provides a busbar preparation method and a capacitor busbar prepared by the busbar preparation method. The structure is simple, and the design is reasonable and easy to realize. The problem that the connection terminal and the busbar substrate are difficult to assemble is solved; the welding production efficiency is greatly improved; and the rejection rate caused by unstable welding is effectively reduced.