<p>Background: According to previous studies, <em>Anethum graveolens L.</em> (dill) aqueous extracts decreased the fertility of female rats. Therefore, the present study aimed to examine the effects of this herb on cultured granulosa cells and immature oocytes.&nbsp;<br /> Methods: The cells were obtained from 27-29 day immature superovulated mice. The oocytes were cultured in a petri dish consisting of 30 <em>&mu;l </em>drops of MEM-&alpha; and granulosa cells in a 24-well plate consisting of DMEM/F12 and different concentrations of 0, 10, 50, 100, 500, 1000, 10000 <em>&mu;g/ml </em>of dill seed aqueous extract (DSAE) in 37^o<em>C</em> and 5% CO₂. Then, the <em>in vitro</em> maturation of oocytes, including Germinal Vesicle (GV), Germinal Vesicle Breakdown (GVBD), and meiosis ІІ (MІІ) and oocyte bioviability were determined. Granulosa cells were then extracted and their bioviability, apoptosis, chromatin condensation, and lipid synthesis were examined. Estrogen and progesterone concentrations and Alkaline Phosphatase (ALP) activity were measured by RIA and spectrophotometry respectively from the supernatant of granulosa cell culture.<br /> Results: The results revealed that concentration of 10000 <em>&mu;g/ml </em>of DSAE were toxic and damaged granulosa cell growth and oocytes maturation. Lower concentrations were the same in the control group and did not have any side effects on cell growth. The number of lipid droplets, estrogen and progesterone concentrations, and ALP activity increased with higher doses of DSAE compared to those in the control culture. Additionally, apoptosis and chromatin condensation increased in higher concentrations of DSAE-(500 and 1000 <em>&mu;g/ml</em>) treated cells. This herb extract decreased the oocytes maturation in dose-dependent manner.&nbsp;<br /> Conclusion: It was concluded that DSAE increased granulosa cells activity but damaged oocytes maturation, therefore it might be introduced as infertility agent.</p>