Abstract With a substantial improvement in machine translation systems and an increasing demand of translations, post-editing of machine translated texts has become a common practice to obtain a better quality of translation. This thesis presents an investigation into linguistic post-editing rules from the interaction between machine translated texts and manual monolingual post- editing. In this thesis, an experiment is presented in which twenty informative texts translated by Google Translate are post-edited by six post-editors. Unlike the traditional bilingual post- editing, post-editors in this experiment have no access to the source texts. The edits are analyzed based on Baker's concept of equivalence in translation. A qualitative evaluation on fidelity has been carried out to test if the post-edited Google Translate output deliver the meaning of the source texts. Based on data analysis and quality assessment, the results show that: a) monolingual post-editing can help yield readable translations that deliver much of the same message in the source texts; b) the commonly used linguistic post-editing rules for economic and political documents mainly include correct incorrect verb forms, correct mistranslation of word, correct incorrect word order, segment long sentence, delete redundant word. Other rules that are worthy of attention are: make incomplete sentence complete, correct collocational patterning, compensate for lack of subject, resolve cohesion issues, resolve issues of number forms, specify general terms, compensate for lack of conjunctions, change preposition, correct misuse of punctuation mark, lexicalize the ST, correct sentence restructuring, correct incorrect noun forms. It should be made clear that this pilot study is an attempt to understand commonly used linguistic post-editing methods so as to summarize post-editing rules applicable to political and economic texts translated by Google Translate. Key words: Google Translate, Monolingual Post-editing, Political and Economic Texts