Abstract: Gas chromatography-Fourier transform infrared spectroscopy technique (GC/FT-IR) integrates the excellent separating power of GC and the structural information of IR. Based on GC and IR spectra, complicated products can be analyzed quantitatively and qualitatively. Dewaxer DF-1 is a complicated product of more than 20 components. It consists of aryl compounds and saturated or unsaturated alkanes. The main components of DF-1 was determined by GC/FT-IR technique.