In this paper we atempt to think if it is possible to conceive age as a characteristc time of living organisms including man. In the paper we review several concepts of age coming from sciences such as chronobiology, gerontology, evo-lutonary biology and developmental biology, and trough all of them, we see that biological time is thought as time measured by a clock. We propose that age as biological time must be understood as a phase in the biological process, but depending on the complete cycle of the organism. In the case of human being, his age is determined also by what is "expected" about him. His age is then determined by biological and cultural aspects.