A new synthesis method of porous zinc was developed through protein foaming route. The foaming process can be divided into three steps: slurry mixing, low temperature foaming and high temperature sintering. Different ambient pressure was used at low temperature foaming step to adjust the morphology and pore size of the porous zinc. The microstructure analysis indicated that both the average pore size and porosity increased as the pressure reduced from 100 kPa to 10 kPa. This was attributed to the rising expansion rate under low pressure. Moreover, the compression results showed that the strength of porous Zn increased to 6 times as the pressure reduced to 10 kPa. It means that the porous Zn with low density has much higher compressive strength. It can be attributed to the much denser pore walls that achieved through low pressure foaming. In addition, the stress–strain response indicated an apparent brittle shear fracture mode for porous Zn in this work.