The invention relates to a vinyltetrazole and acrylic acid copolymer and a derivative thereof, and belongs to the technical field of polymer synthesis. The copolymer is prepared by a method according to the following steps of sequentially adding polyacrylonitrile, ammonium chloride and sodium azide into a mixed solution of water and DMF(dimethyl formamide); performing heating and stirring reaction; adding diluted hydrochloric acid into the reacted mixed solution; performing stirring until white precipitates are completely separated out; washing the precipitates by water to obtain vinyltetrazole and acrylonitrile copolymers; adding the vinyltetrazole and acrylonitrile copolymers into a sodium hydroxide solution; performing heating and stirring reaction; adding a diluted hydrochloric acid water solution into the reacted sodium hydroxide solution; performing stirring until white precipitates are completely separated out; washing the precipitates by water; drying the precipitates to obtain the vinyltetrazole and acrylic acid copolymer. The vinyltetrazole and acrylic acid copolymer takes further reaction with a sodium hydroxide solution, a potassium hydroxide solution or ammonium hydroxide, and the corresponding sodium salt, potassium salt or ammonium salt is obtained.