Anthocyanins, total phenolic compounds and antioxidant activity of the extracts of purple corn cobs were evaluated in the investigation. The extractions were carried out in ethanolic solutions to 20% and pH 2 conditioned according to a factorial design with the factors temperature and times both in 4 levels. The results indicate anthocyanins between 11.567 and 37.127 mg/g cob, total phenolic compounds expressed as GAE between 23.426 and 76.962 mg GAE/g cob, and DPPH remaining between 17.06 and 68.80 %. The analysis of lineal regression indicates highly significant dependences between the antioxidant activity and total phenolic compounds (r2 = 0.9974). © 2009 The Authors.