The invention discloses a preparation method of a Bi-2212 high-temperature superconducting wire. The method comprises the following steps: step one, placing Bi-2212 precursor powder into a silver tubeand carrying out drawing to obtain a single-core wire; step two, carrying out cutting, bundling and tubing, and drawing on the single-core wire to obtain a secondary composite wire and then carryingout the cutting, bundling and tubing, and drawing again to obtain a Bi-2212 wire; step three, carrying out partial melting and thermal processing on the Bi-2212 wire; and step four, carrying out low-temperature heat treatment on the Bi-2212 wire after the partial melting and thermal processing to obtain a Bi-2212 high-temperature superconducting wire. According to the invention, with the mode of carrying out the partial melting and thermal processing and then carrying out the low-temperature heat treatment, more effective magnetic flux pinning centers are formed in the Bi-2212 wire, so that the high temperature superconducting performance of the Bi-2212 wire is improved and a problem that the performance of the Bi-2212 wire is affected by the Bi-2212 grain boundary deviation due to the element doping method is solved.