Khajeh Nezam al-Molk in his book of Siasatnameh has covered an ideological and religious discussion to consolidate the pillars of governance in the reign of Seljuk dynasty. The author of Siasatnameh is highly prejudiced in his book in favor of Shafi’i and Hanafi sects, among the common faiths in the period. He addresses the followers of other faiths and sects with insulting terms such as “people of bad religion” and “people of bad faith”. To exert more influence on his readers and justify his opposition to religious opponents – his political opponents per se – he has included anecdotes according to each subject matter. Dissidence and encountering the opponents in Siasatnameh are the two issues this paper is an attmept to explain, analyze and explain through Fairclough’s critical discourse analysis. Discourse analysis studies the way of manifestation and formation of meaning and message of linguistic units in connection with contextual elements. The evolutional survey of discourse analysis leads to critical discourse analysis that has its roots in critical linguistics. In the meantime, the critical approach of Norman Fairclough is the most comprehensive framework for critical discourse analysis. In this paper, we will first explain Khajeh Nezam al-Molk’s thoughts and views vis-à-vis his political opponents through the context and anecdotes, then we will explain and analyze the findings based on Fairclough’s method. The paper is an attempt to find an appropriate response to the question of how Siasatnameh treats its religious opponents. The response to this question has been provided by using Fairclough’s critical discourse analysis method and analyzing the hidden layers of Khajeh Nezam al-Molk’s thoughts.