Argument and proof are of special importance in mathematics education at all levels of education, from school to university, and it is almost impossible to understand and understand mathematics without emphasis on argument and proof. In this study, which is based on the method of uncompleted context, the goal of the researcher is to investigate students' understanding of the process of making mathematical proofs and also to investigate their attitude towards mathematical proofs. The studied sample is 50 male and female undergraduate students of two Rabazi Azad Universities, Shebstro Azad and Sufian Azad, which is considered an accessible sample. The measurement tool in the current research is a questionnaire, which contains two main parts. In this section, a rod with its proof was presented and then the students were asked to answer the questions about the process of making the proof. Also, the design of the second part of the questionnaire is based on the studies conducted in the background of the research and the results of the research of other researchers in the field of the objectives of mathematical proofs and students' problems in reasoning and proof. This model examines seven different levels of students' understanding of the process of making mathematical proofs. The local aspect of proof emphasizes the understanding of basic concepts and the relationship between propositions and theorems, but the general aspect of proof pays more attention to the main methods of proof and its application in other concepts.