Backgrounds: Next to hard tissues like bones, teeth and nails, hair is stable under adverse natural conditions. Hence, hair are recovered along with other skeletal remains and sent for examination. Here the question often asked is whether the hair is of human or not? Aims: The present study is carried out to find the most reliable quantative parameter for differentiation of the human hair from the animal hair. Materials & Methods: Hair samples from various species of animal and various sites of human hairs were obtained. In the present study the diameter of shaft, diameter of medulla and the medullary index of the human and different animal hair were measured. It was found that, medullary index, which was less than 0.25 in human hair and more than 0.44 in animal hair is useful parameter to distinguish between human and animal hair.

Key Words: Human & animal hair, Diameter, Medullary index, Forensic application.