One of the new issues in the field of Qur'anic research is the translation of the Qur'an. This movement, with its many strengths, also has weaknesses. One of these weaknesses is equivalence of Quranic words, among which one can refer to the word of " Zann: suspicion" as one of the most used and challenging words in the Qur'an. The present study uses a descriptive-analytical method with the aim of achieving or inventing the correct viewpoint in the semantics of the word of "Zann" and providing a method in the historical conceptualization of vocabulary to collect, analyze and evaluate the views of the native speakers and commentators. Finally, by evaluating the contemporary and famous Persian translations of the Quran (Ayati, Reza'i, Safavi, Fuladvand, Mojtabavi, Meshkini, Ma'azi, Mesbahzadeh and Makarem Shirazi), their weaknesses and strengths in translation have been evaluated.