In this paper, P(NIPAm-AA-NMA) microgels were synthesized with N-isopropylacrylamide (NIPAm), acrylic acid (AA) and N-hydroxymethylacrylamide (NMA) by free radical emulsion polymerization. Then 4'-aminobenzo-18-crown-6 (ABC) decorated P(NIPAm-AA-NMA) microgels〔P(NIPAm-AABC-NMA)〕were prepared by using N-(3-dimethylaminopropyl)-N'-ethyl-carbodiimide hydrochloride (EDC) as condensation agent. Finally, the P(NIPAm-AABC-NMA) microgels self-assembled films were fabricated by the solvent evaporation method. The microstructure of microgels and self-assembled films were characterized by FTIR, SEM and DLS. Moreover, the temperature-sensitive properties of self-assembled films and their selective response to metal ions were investigated by UV-Vis. The results indicated that the particle size of the microgels before and after decoration by ABC was about 240 nm and 300 nm, respectively. With variation of environmental temperature or concentration of heavy metal ions, the particle size of the microgels in the self-assembled film changed accordingly, the incident light could be diffracted by the self-assembled film, and different structural colors of the film could be observed. In particular, when the Pb2+ concentration changes between 0 and 120 μmol/L, the red-shift of the self-assembled film diffraction peak was about 60 nm.