In this experimental study a test was carried out on a paraffin wax-copper (PWC) thermal properties, which consists of a phase change material with 10% copper powder. The PCW with rectangular shape (25cmΧ 25cmΧ30cm) size is supplied with heater within it, and installed inside an isolated tank case, which allows the water to flow over the PWC from inlet side to the outlet side. This sample isused as a thermal storage .The PWC is initially heated by electric heaterreaching liquid phase at temperature (90°C) while the supply water temperatureranged (19-20°C). An engineering equation solver (EES) computer program has been developed to compute the parameters (outlet water temperature; heat transfer rate, and the time required to release all the thermal energy). The results showed that the outlet water temperature gained due to thermal storage in the water tank (PWC) is more than with (PCM) which consists of paraffin wax without copper powder. The water temperature decreases with the increase of water mass flow rate and the freezing time for this sample takes long time interval for the lower mass flow rates. The ratio of the thermal storage for mixture paraffin wax increased by 30.7% compared with a normal wax pure.