Conceptual socialization refers to the process second/foreign language learners go through to transform their conceptual system so as "to fit the functional needs of the new language and culture" (Kecskes, 2002, p. 157). Therefore, the present study examined Turkish EFL learners' conceptual socialization by analyzing the similarities and differences between native speakers of English and Turkish learners of English in their request speech acts realization. The data were collected from Turkish learners of English (focal group) and native speakers of English (baseline group) through role-plays and a written discourse completion task on requests both in Turkish and English. Participants' responses were rated in terms of the level of formality, politeness, directness and appropriateness. The results indicated that although the Turkish EFL learners were higher level learners, they could not produce the required level of politeness, formality and appropriateness in their speech acts as much as the native speakers did. This study reveals that in EFL contexts, where there is lack of authentic social interaction and engagement with a community of practice, language learners' "conceptual socialization" process is bound to their experiences of classroom instruction and L1 socialization.