This study aims to explore the creative mathematical reasoning process of climber students in solving Higher Order Thinking Skills geometry problems. The results showed that the climber students met the criteria for basic mathematical creative reasoning in solving problems, namely the plausible and novelty criteria. However, there are times when climber students do not meet the requirements for novelty because their accuracy and creative mathematical reasoning thinking have not been used to solve problems, even though climber students tend to like challenges and do not give up on solving problems.