Estrogen attenuates food intake and enhances c‐Fos expression in the suprachiasmatic nucleus (SCN) specifically during the light phase in ovariectomized rats, and also has the antidepressant effect. Serotonin (5HT) neurons play an important role in the food intake, the pathogenesis of depression, and the formation of circadian rhythm. To test the hypothesis that 5HT is involved in the anorexigenic and antidpressant effects of estrogen, we examined the effect of selective serotonin reuptake inhibitor (SSRI) administration on food intake, depression like behavior and c‐Fos expression in the SCN in ovariectomized rats. Rats were ovariectomized and implanted either with an estradiol (E2 group) or a cholesterol (Veh group) containing silicon tubing. SSRI was injected at the beginning of the light and dark phases for 10 days. SSRI attenuated the food intake specifically during the light phase in the both groups, and reduced depression‐like behaviors in the Veh group. The number of c‐Fos like immunoreactive cells in the SCN during light phase was larger in the E2 than the Veh group, and SSRI increased the c‐Fos expression in the ventrolateral SCN only in the Veh group. These suggest that 5HT is possibly involved in the estrogen‐induced anorexigenic and antidepressant effects by changing the response to photic stimulation.