A new type of polymer gel that eliminates the oxygen chemically instead of using complicated facilities was recently introduced. This study utilized a polymer gel fabricated in a laboratory as a reliable dosimeter for measuring therapeutic radiation. Studies on the optimal MR scan conditions was conducted. The reproducibility, the accuracy, and the dose rate dependency of the normoxic polymer gel dosimeter were evaluated. The relative dose uncertainty and the relative dose resolution of the polymer gel were also evaluated by scanning it under optimal MR scan conditions. The R2 calculated by using echo time (TE) of 20, 40, 60, 80, and 100 ms versus dose was linear for 12 ∼ 20 Gy. The polymer gel composed in this study can be used as a reliable dosimeter if it is scanned under optimal MR scan conditions.