<![CDATA[This study aims to analyze the relationship between mathematical reasoning and mathematical problem-solving skills among elementary school students. Mathematical reasoning is an essential competency in mathematics education, playing a key role in helping students understand concepts, construct logical arguments, and determine systematic problem-solving strategies. The study employed a quantitative approach with a correlational design. The participants consisted of 59 fifth-grade students from SDN Kanigoro in Kartoharjo District, Madiun City, East Java, Indonesia, selected through purposive sampling. Data were collected using mathematical reasoning and mathematical problem-solving tests with established validity and reliability (content validity index = 0.92; Cronbach's alpha = 0.88 and 0.91). Data were analyzed using Pearson correlation and simple linear regression. The results revealed a very strong positive relationship between mathematical reasoning and mathematical problem-solving skills, with r = 0.874 and p < 0.001. Furthermore, the coefficient of determination (R² = 0.763) indicates that mathematical reasoning accounts for 76.3% of the variance in students' mathematical problem-solving scores. These findings suggest that higher mathematical reasoning skills correspond to better performance in solving mathematical problems. The novelty of this study lies in providing empirical evidence from the elementary school context that quantifies the substantial proportion of problem-solving performance explained by mathematical reasoning through a correlational approach. Therefore, fostering mathematical reasoning should be a primary focus in elementary mathematics instruction to enhance students' mathematical problem-solving capabilities.]]>
