This study attempted to investigate whether there was a relationship between students' socio-economic background and their instrumental and integrative motivation. The subjects in the study were students from two English-medium universities, Bilkent University and Middle East Technical University (METU), who were studying in the preparatory schools in order to become proficient in English prior to entry to their respective departments. The 50 female and 50 male students who were between 17 to 28 years of age were randomly selected for the study. Two instruments, a socio-economic background (SEB) questionnaire which aimed at identifying four different levels of SEB, and a instrumental and integrative motivation scale were used to assess the subjects' SEB and the two types of motivation. In order to test the hypothesis of the study two statistical procedures were used: A Pearson product-moment correlation coefficient and a one-way analysis of variance (ANOVA). The results showed that instrumental motivation was highly related to the upper levels of SEB. Integrative motivation was not significantly related to SEB. A further investigation was carried out in order to find out whether SEB of males and females was significantly related to instrumental and integrative motivation. The findings suggest females of the upper SEB levels showed a high level of instrumental motivation. There was no relationship between females from lower SEB levels and the two types of motivation. Likewise, there was no relationship between males from all levels of SEB and the two types motivation.