Animal glue is a traditional material used extensively as adhesive and binder in mother-of-pearl, wooden structure, traditional painting, etc. Analysis of animal glue is usually performed with IR(infrared spectroscopy) based on the IR absorption of functional group. But, it has a limitation in confirming animal glue when a sample consists of several materials because of overlapping of the absorption band. Py/GC/MS(pyrolysis/gas chromatography/mass spectrometry) is a useful tool in analyzing the constituent of polymeric materials like animal glue by identifying their pyrolysate with very small amount of sample. In this study, confirmation of animal glue in a Dancheong sample was tried with this method. Characteristic pyrolytic compounds of animal glue and tung oil used in Dancheong were identified. Dancheong sample painted with Noerok as a coloring material, animal glue and tung oil was prepared and it was possible to find characteristic peaks of animal glue after thermal degradation and artificial weathering experiment. From this, we found that animal glue can be detected using py/GC/MS in cultural heritage samples consisting of several materials and in different condition. IR was also tried to analyze Dancheong sample and the results were compared with those of py/GC/MS for the detection of animal glue.