Abstract: Homocysteine and some related cytokines are involved in Preeclampsia (PE) pathogenesis but their role in progression of the disease is controversial, accordingly the aim of this study was to evaluate maternal serum Homocysteine levels and relate them to tumor necrosis factor-alpha (TNF-α) and Transforming Growth Factor-beta 1 (TGF-β) as predictive tests for the development and progression of preeclampsia. Seventy five pregnant women (30 mild-PE and 30 sever-PE and 15 normotensive pregnant women) were included in this case-control study. Maternal serum Homocysteine, TNF-α and TGF-β 1 levels were measured in the third trimester by immunosorbent assay (ELISA). Homocysteine and TNF-α serum levels were discriminating between sever and mild-PE which suggests them as PE severity biomarker. Homocysteine, TNF-α and TGF-β increased in the PE group than normotensive pregnant group. The combination between them increased their significance. In conclusion, Women with preeclampsia have high serum homocysteine levels that are directly related to TNF-α and TGF-β and can be considered to play important role in preeclampsia progression.