In this study, the visual estimation skills of fourth grade elementary school students based on their mathematical thinking processes were investigated. The research questions focus on understanding how students' mathematical thinking processes influence their visual estimation skills. A total of 445 students participated in the study. The relational scanning model was used to determine the relationship between students' visual estimation skills and their mathematical thinking processes. The Mathematical Process Instrument and the Visual Estimation Skills test were used as data-gathering tools. The data obtained were analyzed using different statistical methods, including the chi-squared test, t-test, and single-factor analysis of variance. The findings contribute to our understanding of the complex relationship between mathematical thinking processes and visual estimation skills in students, addressing the research questions raised in the study. These results can inform educators and instructional designers when developing effective teaching materials and strategies that cater to students' diverse thinking processes.