A curved surface absorber type solar fluid heater having radially spaced curved surfaces, preferably hemispherical and closed at bottom periphery, defining a closed chamber termed as collector which receives a fluid to be heated. The curved surface absorber type solar fluid heater encompasses two radially spaced transparent curved surfaces preferably hemispherical, closed at bottom periphery, placed over collector termed as a glazing, and an insulated hemispherical hot fluid tank, placed within the cavity of inner curved surface of the collector and bottom insulation. A plurality of plumbing connections is made between the collector and the hot fluid tank with arrangement of non-return valves to prevent backflow of fluid from hot fluid tank towards the collector. An air vent is located at the highest position of the collector. A drain plug is located at a lowest position on the collector.