Nowadays olefin/paraffin separation is an energy intensive process via distillation or adsorption. Hence, a new type of mixed matrix membrane (MMM) has been investigated as an alternative separation technology for olefin/paraffin separation. The MMM was fabricated by casting a mixture of silicone rubber and Ag-zeolite on a with/without poly(ethylene glycol) (PEG) treated porous polysulfone support. The permeability and selectivity of ethylene to ethane were determined using the membrane testing unit. Results from the study can be concluded as: 1) Ag-zeolite does not enhance the ethylene/ethane selectivity, 2) PEG enhances ethylene/ethane selectivity, and 3) silicone rubber is not suitable polymer to form Ag-zeolite MMM.