Twice hot-embossing, a new technology of hot-embossing proposed, can effectively reduce the error of hot forming caused by hot equipment. The depth / width ratio of micro-channel on the metal concave-mother-template is an influence parameter of twice hot-embossing; Optimization of the parameters, the PMMA convex-template has been produced in 120°C, ± 6MPa by twice hot-embossing.