Near infrared reflectance spectroscopy (NIRS) was used to discriminate different types of ground beef samples. Fifty-three and sixty-seven samples of longissimus thoracis muscle corresponding to adult castrated steers (over 4 years old) and young cattle (under 14 months old), respectively, were homogenized and scanned over the NIR range (1100-2500nm). The results showed that NIRS could successfully discriminate 100% of ground beef samples depending on the sort of animal, probably as a consequence of differences in the intramuscular fat and water contents. Thus, NIRS is a fast, inexpensive, and non-destructive method that can be used to discriminate these beef products.