The invention relates to a high-efficiency evaporator which comprises a heat exchange tube (1) arranged in a heat exchange chamber (2), and the upper end of the heat exchange tube (1) is fixed on an upper tube plate (3). The high-efficiency evaporator is characterized in that a distribution plate (4) is arranged at the upper part of the upper tube plate (3), a distribution tube (5) is arranged onthe distribution plate (4), an overflow hole (6) is arranged on the distribution plate (4), and the overflow hole (6) is projected at the periphery of a tube hole of the heat exchange tube (1) on theupper tube plate (3); the distribution tube (5) is covered below a cover plate (8), a half tube (7) is fixed under the cover plate (8) in a hanging way, the cover plate (8) is fixed in a feeding chamber (12), a connecting tube (9) which is communicated with an inner chamber of the half tube (7) is arranged on the cover plate (8), the upper end of the connecting tube (9) is not lower than a feeding port (10) arranged on the feeding chamber (12), and a blanking port (11) which can enable materials in the feeding port (10) to flow to the distribution plate (4) is arranged on the cover plate (10). The invention has the advantages of simple structure and high evaporation efficiency.