OBJECTIVE Methoxsalen is a natural photoactive compound which is found in many seed plants. A number of epidermal proliferative disorders can be treated by methoxsalen along with long wave ultraviolet A (UVA). MATERIALS AND METHODS In an experimental study, we aimed to demonstrate the effect of methoxsalen, UVA and their combination on oogenesis Balb/C mice. There were two experimental groups and a control group. The experimental groups were composed of i. a short term group with treatment duration of 15 days and ii. a long term group with treatment duration of 5 weeks. Both the long term and short term experimental groups were further subdivided into a UVA group, a methoxsalen group and a methoxsalen plus UVA group. After treatment, mature females in prosterus phase of ovarian cycle were scarified with ether, while their ovaries were removed and prepared for histological studies. RESULTS Both macro and microscopic studies showed significant anomalies (p<0.05) among experimental group ovaries as compared to control group. The obtained results showed a significant decrease in the following factors: number and diameter of corpus lutei, Graafian follicles, diameter of granulosa cell layer and oocytes, number of primordial and primary and growing follicles, while we observed an increase in number of atretic follicle. Furthermore, our findings confirmed an increase in theca diameter only through UVA treatment. Methoxsalen also reduced circulating estrogen levels in blood serum, significantly. Other cases of teratogenecity, such as follicles with three oocytes and disorganization in corpus luteum cells were observed. CONCLUSION The result suggests that UVA, methoxsalen and their combination cause health problems and cell injuries.