Background: Preeclampsia is a serious complication during pregnancy that affects not only the physical health of the mother and fetus but also the mother's mental health, including stress and depression, which has an impact on her social and community role. Purpose: to investigate the effect of cognitive behavioral therapy on stress and depression among pregnant women with pre-eclampsia. Design: quasi-experimental, nonequivalent control group (pre- and post-test) design. Sample: A purposeful sample consisting of 70 pregnant women was taken in the following settings: antenatal clinics and high-risk pregnancy department of obstetrics and gynecology hospitals affiliated with Cairo University hospitals. Tools: Four tools were used: a sociodemographic data questionnaire, the perceived stress scale, the Beck Depression Scale, and knowledge regarding preeclampsia. Results: At the pretest, there were no statistical differences between the study and control groups in relation to stress level and depression level. But, at the posttest, there were highly statistically significant differences in stress level and depression level among the study and control groups (p = 0.001 and 0.001), respectively. Conclusions: The cognitive behavioral therapy program had a positive effect on reducing depression and stress among pregnant women with preeclampsia. Recommendation: A continuous training program for nurses at a maternity hospital about how to apply cognitive behavioral therapy (CBT) for pregnant women with preeclampsia, stressing that the cooperation between obstetrician and psychiatric experts can help to improve favorable conditions in women during pregnancy