Separation and enrichment of tartrazine on multiwalled carbon nanotubes was performed. Tartrazine was eluted with 10mL dimethylsulfoxide and determined spectrophotometrically. The influences of pH, the amount of analyte, sample and eluent flow rates, and sample and eluent volumes were investigated. The effects of different dye matrices and of some metal ions and anions were examined. Recovery was higher than 95%, limit of detection was 3.4g L-1. The method was employed for determination of tartrazine in tap water, in powdered beverages, and in drug samples.