The invention belongs to the technical field of a macromolecular polymer, and discloses a multi-component polymerization method based on alkyne and sulfonyl azide as well as a sulfonyl-containing polymer and application. The multi-component polymerization method comprises the step of performing multi-component polymerization reaction on a binary alkynyl compound, a binary sulfonyl azide compound and a third component compound under the protective atmosphere and through the effect of a univalent copper catalyst to obtain the sulfonyl-containing polymer, wherein the third component compound is acyanophenyl compound containing hydroxyl or amino, a formyl-containing thiophenol potassium compound, an amino-containing benzoyl compound, ammonium salt, ammonia, thiocyanate or selenium cyanate. The method is mild in polymerization conditions, simple in process, high in polymerization efficiency, large in product molecular weight and high in atom economy; furthermore, a functional element containing the complex structure can be constructed in situ simply and efficiently. The obtained sulfonyl-containing polymer is applied in the fields of fluorescence detection, metal ion detection, organicphotoelectric materials and antibacterial materials.