The Universal Attenuated Total Reflectance Fourier Transform Infrared (UATR-FTIR) with a ZnSe-Diamond composite crystal was used to analyze contaminated cotton fibers. Cotton fibers were selected based on their High Speed Stickiness Detector (H2SD) readings. All cotton samples were tested sticky and their H2SD readings ranged between 24 and 72.2 sticky spots. Trehalulose (the dominant sugar in the whitefly honeydew contamination) was identified at 3280 cm-1, 1622 cm-1, and 1018 cm-1. Seed coat fragments and seed meat were identified at 2850 cm-1 and 2918 cm-1. The results obtained showed that the ZnSe-Diamond composite crystal FTIR accessory could be used as fast and precise nondestructive method to determine the origin of cotton contamination.