Vocabulary is divided into receptive vocabulary and productive vocabulary. Receptive vocabulary is the vocabulary which is obtained through reading and writing. This kind of vocabulary may affect students’ productive skill. Productive skill refers to all products of language skills, one of them is paraphrasing. Thus, the researcher is wondering whether there is a correlation between students’ receptive vocabulary size level and their productive knowledge, especially paraphrasing ability. The aims of this research were to know (1) the receptive vocabulary size level of EED of UMY students, (2) the category of EED of UMY students’ paraphrasing ability, and (3) the correlation between students’ receptive vocabulary size level and their paraphrasing ability. The data were collected from 38 students of EED of UMY batch 2016. This research used 14,000 words receptive vocabulary size test from Nation and Beglar (2007) with the reliability 0.873 which means it is highly reliable. The result of this research showed that the students’ receptive vocabulary size level is in low category as it was shown by the mean 4773,6. On the other hand, students’ paraphrasing ability belongs to good category with the mean 1,22 of 2. By ρ = 0.011 and r = 0,410, it means that there is a positive, significant, and moderate correlation between students’ receptive vocabulary size level towards their paraphrasing ability.