The purpose of this study was to examine the proportional reasoning skills of Turkish middle school students. It was also aimed at revealing the differences in students' performances in terms of their gender, grade level, and problem types--missing value and numerical comparison. The study was conducted with two sixth and seventh grade classes from a public school in Ankara, Turkey. The data were collected through a proportional reasoning performance instrument consisting of eight ratio-proportional tasks--three missing value and five numerical comparison problems. The results revealed that there were differences in students' performances according to the type of problem and their grade level. Students were more successful in solving missing value problems than comparison problems. Also, it was found that seventh grade students performed better than sixth graders.