Recent language testing research investigates factors other than language proficiency that may be responsible for systematic variance in language test performance. One such factor is the test takers' cognitive styles. The present study was carried out with the aim of finding the probable effects of Iranian EFL learners' cognitive styles on their performance on communicative tests. For purposes of the present study, it was hypothesized that field (in)dependence would introduce systematic variance into Iranian EFL learners' communicative-test performance. 240 junior and senior students all majoring in English took the Group Embedded Figures Test (GEFT), the 1990 version of IELTS, and the Communicative Test (CT) designed for the present study. The results of the present study provided evidence that the field-dependent (FD) subjects, compared to their field independent (FI) counterparts, performed much better on the CT. It was, therefore, concluded that test takers' cognitive styles may be viewed as a source of systematic variance in performance on communicative language tests.