Pervaporation(PV) is a membrane process which is originally used in industries for removal of water from organic solutions or organic from water. Since the PV is a heat driven separation process, it is possible to be used in vapour absorption heat pump systems to concentrate the working fluids. Use of the PV for absorption system has some potential advantages: compact in volume and selectivity to components of solutions. This can be archived by choosing proper working fluids and membranes. In this investigation, two types of the PV membrane modules (dense and porous) with different working fluids were experimentally tested to find out the relation between the membrane and the working fluids in permeate flux. The results show that the PV can be an alternative method to concentrate working fluids for vapour absorption heat pump systems. However, the performance of such systems largely depends on permeate flux of the refrigerant in the membrane, which is a combination effect of the membrane and working fluid.