The purpose of the study was to determine the association between van Hiele geometric thinking levels and circular achievement exam results for middle school students in 7th grade. The design of the study was a survey method. 157 middle school students were participated into study from three different schools in Kayseri in the spring semester of the 2017-2018 academic year. Van Hiele geometry thinking test which was developed by Usiskin and adapted into Turkish by Duatepe (2000) and a circle achievement test that was developed by the researcher were used to collect the data. Pearson The circle achievement test and van Hiele geometry thinking levels were correlated to find their link. Assumptions were met, hence independent groups t-test and ANOVA were performed. The results revealed that Grade 7. Students van Hiele geometric thinking levels were lower than expected levels. A moderate correlation was found between the circle achievement test and the van Hiele geometric thinking test. The results obtained from the van Hiele geometry thinking test showed statistically significant mean difference across schools 1 and 2. Moreover, there is no statistically significant mean difference across schools at the circle achievement test. Boy and girl middle school students' geometry thinking levels and circle achievement test scores were not statistically significantly different from each other.