Molecular dynamics simulation is a powerful tool in the study of polymeric systems. Among various simulation methods, coarse-grained (CG) model is particularly impactful because it effectively reduces the computational complexity and enables the simulation of large-scale polymer systems. In this review, we briefly summarize recent progresses in our group on the development of CG simulation methods, models, as well as in the software development. By compiling the CG models and various simulation methods, we have successfully developed a GPU-accelerated large-scale molecular simulation toolkit (GALAMOST), which provides an efficient platform for polymer simulations. We further developed the new-generation PyGAMD (Python GPU-Accelerated MD Software, website: http://pygamd.com/) software based on the Python platform, which makes the polymer simulation more powerful, flexible and user-friendly. In addition, some recent application cases in different polymer systems are also introduced. The aspiration of this review is to assist researchers in understanding the role of molecular simulations in the design and development of advanced polymer materials not only for academic researches, but also for possible industrial applications.