The constant hot temperature flat massage ball comprises one top shell-shaped receptacle, one bottom shell-shaped receptacle and a central heating unit which is either a hot water bag, which has circulating water tube, a water pump and a precision temperature control hot water reservoir equipped with a thermostat, or an electric heating pad, which has an electric cord and a thermostat. The top shell-shaped receptacle has a central recess to store the heating unit and a circular female threaded wall at the upper portion of central recess. The bottom shell-shaped receptacle also has a central recess to store the heating unit, a circular male threaded embankment above the central recess to screw into the above-mentioned circular female threaded wall and a groove which is built transversely across its wall and the above-mentioned male threaded embankment to admit the above mentioned circulating water tube and electric cord. The water bag of the above-mentioned central heating unit is heated by hot water, which is pre-heated to 100 to 104 degree Fahrenheit controlled by a thermostat in precision temperature hot water reservoir, through the circulating water tube pumped by a water pump. The central electric heating pad has a thermostat which is preferably adjusted at 100 to 104 degree Fahrenheit. The constant hot temperature flat massage ball is constantly heated by hat water bag or heating pad. Therefore, it can be used for continuously massage with massage body cream or lotion without interruption.
