This article is primarily bidirectional in that it is concerned with two cognitive styles of field-dependency/independency on the one hand and breadth of vocabulary knowledge on the other hand. In other words, the present research primarily intends to investigate the nature of the students' vocabulary knowledge in the field of passive and active knowledge of L2 words as a whole with regard to their preferred cognitive style of field-dependency/independency. A group of 60 undergraduate students majoring in the field of English translation was selected. They were then divided into two groups on the basis of their preferred cognitive styles of field-dependency/independency. Four types of tests, the 1000 frequency Word-Level Test, the passive version of the Vocabulary Levels Test, the productive version of the Vocabulary Levels Test, and the Group Imbedded Figures Test were administered to the participants. The conclusion drawn after the analysis of the data was that the participants in the field-independent group outperformed their field-dependent counterparts regarding both passive and productive vocabulary levels. Finally, the findings of this piece of research could be interpreted as being supportive of the idea that the cognitive styles of field-dependency/independency could be considered as an effective factor influencing the learners' vocabulary learning.