The cycle time of conventional hot embossing can reach as long as 10 min due to its periodically heating and cooling steps. In recent years, researchers around the world had made great efforts to deal with this problem but still some unsolved defects left. To shorten the cycle time and reduce the energy cost therein, we proposed a new type of plate to plate isothermal hot embossing method with a cycle time down to 20 s as practical. The primary difference between two methods was the thermal pattern, that the mold temperature of our new method remained constant and uniform at a relatively low level throughout the whole process. After specific experimental device was designed and built up, polypropylene (PP)a kind of representative semicrystalline polymerwas chosen as experimental material. In this article, the feasibility and internal mechanism of our method were discussed. The influence of mold temperature, pressure, and holding time on the replication precision of micro V-cuts were studied. Furthermore, a promising application of PP products in the field of microstructure heat exchangers was also introduced briefly. POLYM. ENG. SCI., 58:952-960, 2018. (c) 2017 Society of Plastics Engineers