Proof is at the heart of the mathematics and also it is an essential tool for promoting mathematical understanding. Previous studies show that students often have difficulty in the proving process and they don't enjoy the activities involving proving. Hence, the aim of present study is to determine students' perception about proving through metaphors at the university level. For this purpose, the study was conducted with 96 undergraduate students from mathematics department of a state university in Turkey. The findings of the study show that source and reason of the metaphors which were used by the students were mostly about the clarification function of proving. The results of the study are discussed and compared with the literature, and suggestions have been made for new studies in this direction (abstract by the author).