Conservative members of parliament and clergymen in the fifth Majlis of the National Consultative Assembly [Majles-e Shoura-ye Melli] who were among the opposition of Reza khan, the prime minister, have assessed the Republicanism plan of Reza khan. After the evaluation of the plan, they regarded it basically as Reza khan’s and his modernist defenders’ first political upheaval for establishing a secular state and gradual removing of the clergymen from the political power structure of the country, and since they considered the plan inconsistent with the principles of the Constitution and also considered it as Reza khan’s first measure to abolish the sovereignty of the Qajar dynasty and to establish his absolute monarchy, they insisted on preserving the principles of the Constitution and the Qajar monarchy. Despite their criticisms against Qajar monarchs because of those monarchs’ approach to prevent the necessary political changes in the country, those parliament members and clergymen decisively opposed the ratification of the Republicanism scheme in Majlis and the promotion of Reza khan’s political base. In this article, a descriptive-analytic research method has been applied. Besides surveying the development process of Reza khan’s Republicanism plan and the causes of its failure, it has been attempted, at the same time to present a brief portrayal of Mohammad-Taqí Malek o-Sho'arā Bahār's pathological view toward the Republicanism scheme and his political role (as one of the important leaders and representatives of the minority fraction of the fifth Majlis) and the reasons of his oppositions toward the ratification of the plan in Majlis with an emphasis on his historical and literature work (Tarikh-e Mukhtasar-e Ahzab-e Siyasi dar Iran and Divan-e Asha’ar).