Technical Abstract: The high demand for cotton production worldwide has demonstrated the need for its standardized classification. Cotton trash can become comingled with lint during the ginning and harvesting processes. The conventional instrumental method presently used in the United States and other countries to determine many characteristics of cotton is the Uster® High Volume Instrument (HVI) system. The HVI system is very effective in the determination of length, strength, micronaire, color, and total trash content in a cotton sample. However, one limitation of this method is the lack of specificity in the identification of individual trash components (leaf, etc.). A program was implemented to develop novel techniques in order to distinguish the individual types of cotton trash from the lint. In this study, the concept of monitoring differences in spectral bands of cotton and cotton trash by Fourier-transform Near-Infrared (FT-NIR) spectroscopy was demonstrated. A spectral library based on NIR spectral data and pre-processing methods was developed using cotton and cotton trash samples of hull, leaf, seed coat, and stem. The FT-IR method is easy of use, has a short analysis time, and exhibits distinct spectral differences for each type of cotton trash. Further, the FT-NIR spectral library presents a complimentary method to the widely used HVI method to classify cotton trash.