Vocabulary learning strategies and vocabulary size are among the main factors that help determine how students learn second language vocabulary. The present study was an attempt to exploring the relationship between vocabulary learning strategies and Arabic vocabulary size of 742 pre-university in Religious High School (SMKA) and Government-Aided Religious School (SABK). TAV test and Schmitt’s (1997) vocabulary learning strategies questionnaire including 5 categories (Determination, Social, Memory, Cognitive and Metacognitive) were used in present study. The major findings of this study were as follows: First, descriptive statistical analyses showed that the most frequent learning strategies was indicated that the most preferred vocabulary learning strategy category of all was related to determination strategies. Social strategies ranked the second. Memory, cognitive and the metacognitive strategies ranked the third to the fifth. Next, pre-university students reported not having the average vocabulary size to accommodate advanced studies at university level. Finally, the findings of the study revealed there was a relationship between the use of vocabulary learning strategies and Arabic vocabulary size.