A Fourier transform infrared (FT-IR) spectrometric method was developed for the rapid, and direct measurement of piroxicam (Pir) in pharmaceutical drugs. Pir is a well known and very effective antiinflammatory drug. Pir can be determined by various methods and now we are adding a new one that uses a Fourier transform infrared spectrophotometric technique. Conventional spectra were compared for best determination of active substance in pharmaceutical formulations. The Beer-Lambert law and two chemometric approaches, partial least squares (PLS) and principal component regression (PCR+) methods, were tried in data processing.