Since using single precision has several potential advantages, an intrinsic question arise, can single precision be implemented for the DMRG numerical calculations? Actually, simply porting the double precision code into single precision is a wrong answer. The single-precision transformation should be carefully designed and examined. In this study, we investigated the DMRG procedure, and developed two types of mixed-precision transformation for DMRG method at two different levels. At a relatively coarse-grained level, we identified the Gram-Schmidt orthogonalization process as a fundamental step, that causes a tremendous loss in significant number and made the full single-precision DMRG strategy to fail. At the fine-grained level, we mainly focus on the mixed-precision transformation of the Davidson diagonalization method and developed an accuracy-preserved method. By combining these two methods, we developed a hybrid mixed-precision implementation for DMRG. In this article, we will first introduce the fundamental procedure of the DMRG method and these two mixed-precision methods in Section II. The benchmark result and some discussions are presented in Section III. In Section IV, some conclusions of this article are summarized.