Schizophrenia is a severe mental disorder affecting behavior, thought and emotions in the form of hallucinations, delusions and cognitive impairment. Dopamine system is implicated in the pathogenesis of schizophrenia through dopamine receptors expression in the brain. The aim of this work is to evaluate the role of mRNA expression of dopamine receptors D2 and D3 in the diagnosis of schizophrenia. Thirty-five schizophrenic patients and fifteen age and gender matched healthy controls were included in this study. Serum lipid profiles were determined by enzymatic colorimetric method while the determination of dopamine receptors D2 and D3 mRNA expression was performed by real time q PCR technique. There was significant statistical decrease of HDL-c and increase of LDL-c in patients compared to control group, while Cholesterol and TAG showed no significant statistical difference between the two groups. There was significant increase of the mRNA expression of dopamine receptors D2 and D3 genes in the blood of the patients compared to control group (p value= 0.001 and < 0.001 respectively). From this study, it could be concluded that Dopamine receptors D2 and D3 mRNA expression in the blood might be used as diagnostic markers of schizophrenia, revealing the importance of dopamine receptors antagonist as antipsychotics.