This paper consternates on four types of lexical relations between English and Arabic, namely, synonymy, antonymy, homonymy and polysemy with regard to translation. Specifically, it aims to shed light on the role of translators in handling these lexical relations. Moreover, it tries to reveal how these relations are reflected both in Arabic and English and if they are causing obstacles while translating. A comparative and qualitative analysis is used to analyse the data gathered from different English and Arabic scholarly and academic texts. The study ends with the conclusion that translators have to pay extreme attention to these lexical relations while translating and exert much effort to come up with a valid translation that uncover the problems resulting from the congruence and ambiguity that such lexical relations impose.