The work aims to investigate a unique membrane-based energy recovery ventilator (ERV) system combined with phase change material (PCM) to efficiently recover thermal energy and moisture between the incoming air and exhaust air from the buidling to reduce the HVAC system load. Heat and mass transfer simulations were conducted for this ERV system under various air temperatures and flow regimes. It has been found that the membrane/PCM based ERV system can achieve sensible effectiveness (heat recovery) of 65% - 98% while latent effectiveness (moisture recovery) of 60% - 80%.