The purpose of this study to evaluate and compare the proprioception of the dominant knee joint at different conditions in normal 20 years of age. The pripriocption was measured at sitting, supine, prone position with the eyes opened and the eyes closed. All were assessed with and without a knee brace around the knee by reproduction the position to which a joint has previously been placed. In this study, 24 rehabilitation therapy major students were assessed at Hansoe University. In this study applied the paired t-test and 1-way ANOVA to determine the statistical significance of results at 0.05 level of significance. The error average of proprioception was $4.65{pm}2.95^{circ}$ with the eyes closed and $4.08{pm}1.14^{circ}$ with the eyes opened in sitting position, $5.56{pm}3.18^{circ}$ with the eyes closed and $4.98{pm}2.99^{circ}$ with the eyes opened in supine position and $5.60{pm}1.64^{circ}$ with the eyes closed and $4.87{pm}2.16^{circ}$ with the eyes opened in prone position. There was no significantly difference the error average between the eyes opened group and the eyes closed group. There was no significantly difference the error average among the three positions. The error average decreased significantly in knee brace group at all conditions.