This qualitative study aimed at describing student verbal interaction verbally through cognitive activities consisting of procedural, disputational, and exploration in solving geometry problems. This research was in the form of students' verbal interaction activities in group discussion which decribe students' thinking process in detail, both the correct and incorrect thinking process, when conveying their ideas to their friends to solve a problem. The data were collected through a video recording and made in the form of dialogue transcriptions. The research results showed that the form of student verbal interaction on the procedural activity namely (1) students conveyed their ideas to their peers without arguing with each other; (2) discussion activities with planning as its nature; (3) students shared information used in problem-solving. The form of student verbal interaction on the disputational activities were (1) students responded to each other ideas, suggestions, or answers between individuals; (2) students defended each other's ideas or answers so that it triggered a group discussion; (3) the activities would end when all the group member have the appropriateness of the thinking process from the discussed problems.