Abstract: The 28 samples from Jiaotan Guan kiln, one sample of mud material in jar from ruins of Jiaotan Guan kiln, one sample of mud material in pool of practice mud, one sample of violet-golden clay near Guan kiln and four samples of glazes and bodies of the modern imitative ancient Chinese Guan porcelain were analyzed by neutron activation analysis(NAA). The contents of 36 elements in each sample were measured. The NAA data were statistically treated by fuzzy cluster method and the trend cluster diagram was obtained. The results show that the raw material origin of the bodies of Jiaotan Guan porcelain is evidently different from those of glazes, the source of raw material of bodies and glazes of Jiaotan Guan kiln are stable, and the iron is assured as main coloring element. The reflecting spectrum and main wavelength of Guan porcelain glazes are determined by color analysis instrument. The relative content of structural iron (Fe~(2+),Fe~(3+)) in the glaze and the quantitative relationship between the main wavelength of glaze in (various) colors are determined by Mssbauer spectrum. Thus the coloring mechanism of Guan porcelain is investigated.