In low temperature co-fired ceramic (LTCC) packaging which offers a good performance to produce multilayer structures with electronic circuits and components, the via-hole fabrication of LTCC ceramic-PET double layer sheets (green sheets or green tapes) by micro-scale punching plays an important role in providing an electric path for the interconnection between layers. Although conventional punching has been used widely and many researchers have provided useful insights of the process, they are restricted to the punching of single layer material. This paper discusses the characteristic of micro via-hole punching of double layer sheets and the optimum process condition for via-holes of good quality. Workpiece (double layer sheet) used in the present investigation consists of LTCC ceramic composite material layer (ceramic layer) of 20~100*m in thickness and PET layer of 38 and 75*m in thickness by tape-casting. The diameter of via-holes ranges from 100~300*m.