Over time, the words change meaning. According to linguistic studies, the most important types of this semantic change are: semantic generalization, semantic appropriation, metaphor and semantic degradation or promotion. This rule also applies to the vocabulary of Arabic; and some of the terms used in the Quran have undergone a semantic transformation. Unfortunately, a number of contemporary Persian translators have neglected this and translated some of the terms in the common and contemporary meaning. This function can seriously damage the Quranic concepts. Since the main religious teachings of the Muslims are taken from the Quran, the slightest error should not occur in the transfer of Quranic concepts to another language. Since some Quran translators have failed to do so in some cases, we have reviewed the errors found in some translations. With the search method in the sources of the vocabulary and the interpretation of the old period, and contemporary dictionaries, we will show the semantic change brought to some Quranic words. Twelve words that have undergone a semantic change have been investigated in 29 Persian translations of the Qur'an and it has been concluded that some translators mistakenly translated those words into contemporary sense.