The development of the anteroventral cochlear nucleus (AVCN) in fetal and infant monkeys (Macaca nemestrina) was analyzed for gross morphologic changes together with growth-related modifications in constituent cell size and cell distribution. Rapid and extensive prenatal volumetric changes were followed by slow and limited postnatal volumetric changes. The time course of packing density and cell size changes paralleled the volumetric changes. At each age the packing density along the rostrocaudal axis of the AVCN was constant except in the youngest specimens (mid- to late-fetal), where local variations occurred. Similarly, the size of AVCN cells along the rostrocaudal axis remained approximately constant at any given age. In comparison with the human and mouse, the macaque exhibits relatively less pronounced postnatal change in overall volume and cellular growth features.