In order to improve the micropores quality obtained by printing copper sheet at room temperature, reduce the internal cracks of the micropores and obtain the micropores with smaller diameters, a new heating-assisted coining process was proposed. Analyzing three aspects of diamond indenter, workpiece grain microstructure and heating temperature,the relationship between the edge crack of the micropore and the three aspects was established, and the imprinting microhole was simulated by DEFORM software.Combined with experimental research,based on the grain refinement analysis of the pure copper by dynamic recrystallization, the optimum process parameters were determined. The results show that the optimum forming temperature and pressing rate are 200 ℃ and 0.01 mm/s respectively.