The utility model relates to a spiral plate heat exchanger, which comprises a heat exchanger main body which is spiral after being rolled up. Spiral heat exchange passages are formed between adjacent spiral coils; a flue side closing plate is arranged at a position where outer rings of the spiral coils are adjacent; a water inlet passage and a water outlet passage are arranged in the heat exchanger main body; and the water inlet passage is separated from the water outlet passage through a flow distribution plate. The spiral plate heat exchanger has the advantages that the cost is lower, the structure is simple, the heat exchange efficiency is high, the spiral plate heat exchanger is resistant to corrosion, the service life is long, moreover, the scale formation is not easy, and the like.