The invention discloses a nitrogen azole metal salt absorbent solution for acid gases and application thereof. The nitrogen azole metal salt absorbent solution comprises, by weight percent, 1-50% of nitrogen azole metal salt and the balance polarity good solvent. The nitrogen azole metal salt is one or optional mixture of imidazolium salt, triazole salt, and tetrazole salt. The polarity good solvent is one of or optional mixture of polyethylene glycol, polypropylene glycol, water, dimethyl sulfoxide, sulfolane, ethylene carbonate, propylene carbonate, glycerol, and polyglycerol. The invention further discloses an application method of the nitrogen azole metal salt absorbent solution for the acid gases. The nitrogen azole metal salt absorbent solution is mainly used for absorbing and separating the acid gases such as CO2, SO2 and H2S, and has the advantages of low cost, high absorption amount, fast absorption / desorption, low desorption energy consumption, high selectivity, reusability and the like.