This study investigates the type of language transfer or cross-linguistic influence in English word order acquisition of Turkish - Dutch bilinguals living in the Netherlands. Word order is looked into with respect to 'topicalization' and 'relative clauses' (RCs). Thus, this is a research on language transfer in third language acquisition (L3A), which, more specifically, seeks answers to the questions of what type of word order transfer Turkish - Dutch bilinguals process in acquisition of English as an L3 and whether they transfer from their L1 or their L2. Grammaticality Judgment Task was carried out for this research on both Turkish - Dutch bilinguals and Turkish monolinguals in Turkey. The results of this research have shown that Turkish - Dutch bilinguals make use of their L2 Dutch rules rather than their L1 Turkish in their English word order acquisition. It has also been found out that Turkish monolinguals are influenced by their L1 Turkish less than Turkish - Dutch bilinguals are affected by their L1 Turkish.