This invention provides a production method of Nb3Al superconducting multifilamentary wire based on rapid-heating, quenching and transformation method, capable of producing a high-performance Nb3Al superconducting multifilamentary wire by improving critical temperature thereof, upper critical field and critical current density. Upon a first stage heat treatment of beating a composite, in which bcc phase Nb—Al supersaturated solid solution is dispersed in Nb matrix, the bcc phase Nb—Al supersaturated solid solution ordered in temperature rise process is made disordered at an initial phase thereof and a non-reacting portion located adjacent is heated using a reaction heat generated when transforming this disordered bcc phase to A15 phase. Then, disordering of the bcc phase is promoted while propagating a high-temperature transformation region so as to automatically progress high-temperature beat treatment. As a result, a reaction-transformation is caused to block stacking fault from being generated in the A15 phase and crystal grain from being coarse and then, a second stage heat treatment for improving a long range ordering of the A15 phase is carried out.