Abstract: Desalination apparatus with the double feature of condensation and evaporation, comprising plural dish-like condensing elements piled coaxially, wherein a sloped bottom diaphragm is provided in each element, at the lower part of each of which an upwardly diverging duct is provided. A cooling pipe is led through the ducts of the elements. A depending pipe is provided near the outer edge of each element, through which the supplied sea water flows from an upper element to a successive lower element. The lowest condensing element is heated or is filled up with water that is hotter than the supplied sea water. The distilled water obtained on each condensing element is withdrawn from the lower edges of the ducts as a result of evaporation from the elements and subsequent condensation on the undersides of the diaphragms.