Thinking is a cognitive activity that occurs in one's mentality (Solso, 1995). In the contextual problem solving, the students are expected to be able to think in order to build the relationship between real situation and prior mathematical knowledge by modeling into mathematics then interpreting the relevant solution by building relationship among the mathematical structures themselves as of the problems can be solved. This thinking process is called the relational thinking process. Relational thinking is always present in human cognition, which underlies the process of thinking about everything from simple to something more complex (Doumas and Hummel, 2004). Jensen (2008: 147-153) stated that there are physical differences between male and female brains, which can lead to differences in cognitive processing between them. This study aimed to describe the relational thinking process of students in solving the mathematical contextual problem. The results of this study showed that, after reading the problem of the male subject was the context emerged and his attempt to build relationship between the context with the formal situation of mathematics to solve the problem. While the female subject began to count in a certain way then mentions how to look for it.