The investigation of the preserved state of ancient silk fabrics can provide important information for the archaeological study and scientific conservation. Therefore, it is indispensable to develop an accurate and reliable method to measure silk fabrics in order to obtain information on their original materials, aging situation and preserved state. Unfortunately, there are difficulties and limits in analyzing the silk fabrics because of their complex organic composition and the small quantity of sample available. Silk fabrics are easy to age when exposuring to acid or alkali environment and light. After aging, there are changes in the amount of amino acid, crystal degree of thread and structure morphology. The amount of tyramine is much richer among the eighteen amino acids in silk fabrics, and this can be an indicator for measuring the variation of tyramine before and after aging. In this study, samples from an excavated silk fabric of Ming dynasty were analyzed, and mulberry raw silk and tussah silk were selected as contrast samples. Fluorescence electron microscopy (FEM), Fourier transform infrared spectrometry (FTIR), as well as X-ray diffraction (XRD) analytical techniques were used to characterize the matted morphology and crystal degree of the silk fiber. Both thin-layer chromatogram (TLC) and ultravioler-visible spectrophotometer (UV-Vis) were used to identify the typical amino acids and to measure the amount of tyramine. The analytical results indicated that the silk sample of Ming dynasty was a kind of mulberry raw silk, and the silk fiber was loose and broken with a decrease in crystal degree. The amino acids mainly consisted of glycin, alanine, serine and tyramine and their content was obviously reduced. The amount of tyramine in analyzed sample was 13.78% approximately, about 0.37% lower compared with the mulberry raw silk sample. This paper described the preserved stat of the silk fabric in qualitative and quantitative aspects. The combination of FEM, FTIR, XRD, TLC, and UV-Vis provided a reliable method for the analyses of silk fabrics.