The present study aimed to obtain quanti-qualitative data about the follicular ovarian population in Cebus apella females. Seven ovaries were obtained from 4 C. apella adult females. The ovaries were subjected to light microscopy. The number of preantral and antral follicles for each ovary was estimated using the Fractionator method. The preantral follicles were classified into primordial, transitional, primary and secondary follicles. Antral follicles were those that presented an antral cavity. All counted follicles were classified as normal or degenerated. The diameter of the follicles, oocytes and their nuclei were determined to accompany the follicular development. All results were represented as mean ± SE. The number of preantral follicles was 56,938 ± 21,888 and 49,133 ± 26,896 for the right and left ovaries, respectively. The percentage of normal follicles was 80 ± 4.95%. The follicular diameter ranged from 22 ± 0.5 Fm to 61.2 ± 4.0 Fm. Regarding the antral follicles, the number of normal and degenerate follicles per ovary were 60.0 ± 19.0 and 3 ± 1.8 follicles, respectively. The antral follicular diameter was 514.4 + 56.6 Fm. In conclusion, the information obtained in this study can be used as a parameter for subsequent in vivo or in vitro studies about folliculogenesis in non-human neotropical primates of the C. apella species. KEY WORDSOvary, histological study, Cebus apella, ovarian follicles. Estudo histológico de folículos ovarianos de Cebus apella. RESUMO PALAVRAS-CHAVEOvário, estudo histológico, Cebus apella, folículos ovarianos.