• The ciliary body of the human eye serves many vital functions and provides important access to the posterior segment of the globe in vitreoretinal surgery. Although embryogenesis and prenatal development of the ciliary body have been well documented, continuing development of the ciliary body during early childhood has not been studied extensively. We determined the lengths of the ciliary body and pars plana in 76 normal eyes of subjects who ranged in age from 1 week to 6 years. The ciliary body was found to be of substantial length soon after birth; it measured a mean of 3.06 mm nasally and 3.31 mm temporally. Three quarters of the final length of the ciliary body at adulthood was achieved by age 24 months. The growth of the ciliary body is discussed in relation to the growth of the eye.