© 2020 The Authors This article reports initial results of fabricating a tailor-made 3D dosimeter using radiochromic material and a 3D printer. The 3D dose distribution is easily visualized and quantitated as the transparent polymers become colored after irradiation. With this technology, we propose a novel method that uses 3D dosimetry to precisely copy the shape of human organs with our 3D printed dosimeter and help provide more accurate and safe radiotherapy.