The invention relates to a highly stable Tb coordination polymer green luminous material and a preparation method thereof. The chemical formula of the luminous material is {[Tb(HO-MINICA))](C2O4)1.5 2H2O)H2O]}n, wherein the n is larger than 1; and the material can be excited by near ultraviolet to transmit green fluorescence. The preparation method comprises the following steps: firstly, preparing organic carboxylic acid ligand; secondly, preparing precursor solution; and thirdly, synthesizing and preparing luminous powder material. The coordination polymer luminous material containing Tb ion mixed ligand is good in crystallinity, colorless, transparent, nontoxic, pollution-free, high in thermal stability, and good in luminescence property; the raw material is cheap and easily obtained; the preparation procedure is simple, the equipment is simple, and suitable for industrial production; and the material can satisfy the requirement in display application fields including three primary colors lighting, public places display, household appliances, medical biological imagery and the like.