Miniaturization drives the need for developing appropriate technology for microproducts of extremely small geometric features with high tolerances. In this work, the authors have investigated the material behavior and size effect in microextrusion of pure copper and aluminum with different grain sizes. A forward microextrusion assembly has been developed in the first phase of work to investigate the grain size effects. The experimental results are then compared to finite element simulation to quantify force displacement response. It has been found that the simulated deformation load is comparable with experimental results. The influence of size effect in both copper and aluminum showed that the extrusion load and average microhardness of 38 μm and 34 μm are higher when compared to 204 μm and 124 μm. In the second phase of work, an attempt has been made to fabricate the copper microgear (m = 0.416 mm) by the developed extrusion setup. The findings of this work are essential for further development of micro-formed parts and will facilitate in introducing microextrusion for mass production of industrial components.