A water treatment system of coupling a heat pump with multi-effect evaporation that comprises a lithium bromide absorption-type heat pump circulation system, a multi-effect evaporation circulation system and a compression-type heat pump circulation system is provided. The vapor in a tail-end evaporator of the multi-effect evaporation circulation system is introduced into a generator in the absorption-type heat pump to release heat and condense. A dilute solution in an absorber of the absorption-type heat pump is introduced into a first-effect evaporator to be evaporated by a treated water, and a condensation heat of the vapor generated by the generator of the absorption-type heat pump is recovered by an evaporator of a compressor heat pump, and another air source evaporator absorbs heat from ambient air to supply heat for the generator by a heat pump condenser.