Guava leaves are used as medicine, among others, for blister burns and wounds, overcome ulcers and colds. Red guava leaf extracts 40 mg/ml/day and 80 mg/ml/day can reduce the number of spermatids in male white mouse models. The effect on spermatogenesis is caused by the content of guava leaf extract namely alkaloids, flavonoids, tannin, essential oil, avicularia, oleanolic acid, saponin and beta-sitosterol. Saponins have an effect especially on cells that develop like during spermatogenesis and oogenesis. The study aimed to determine the effect of guava leaf extract on the process of oogenesis, especially on primary, secondary, de graf and atresia follicles. Method : pre-experimental study used guava leaf extract 4mg / ml which was given orally every day to adult female mice for 4 weeks. A total of 10 mice were divided into 2 groups with 5 mice of each. The two groups were K for control and P for treatment. Each of the mice was sacrificed for their ovaries. The tissue processed by the Paraffin method was then prepared and stained with Hematoxylin Eosin in order to assess the number of primary, secondary , degraf and atresia follicles. The data were analyzed descriptively The results of the study are as follows: the average number of follicles in normal animals without treatment is as follows primary 58, secondary 18, degraf 4 and atresia 48. The average number of follicles in the animals treated (P) is primary 38, secondary 24, de graf 2 and atresia 61 Conclusion: The administration of methanol extract of guava leaves with a dose of 4mg / ml daily for 4 weeks affects the number of primary, secondary, degraf, and atresia follicles.