The invention discloses a printing preparation method and device of a printed circuit. The method includes: obtaining a vector graphic file; identifying a first vector graph source contained in the vector graph file; judging whether there is overlap between the first vector map sources, and fusing the overlapped first vector map sources to obtain at least one second vector map source; generating aprint trajectory from at least one of the second vector map sources; and forming a printed circuit by printing a molten low melting point metal on a printed substrate in a temperature environment nothigher than a melting point of the low melting point metal according to the printing trajectory. The invention re-integrates the vector map source before generating the print track, thereby eliminating the overlapping area, and ensuring that the problem of scratching the metal is avoided in the drawing process.