A shell-and-plate heat exchanger, comprising: a shell forming an internal space, wherein the shell is arranged so that its longitudinal direction coincides with a lateral direction, and has one end in the longitudinal direction as a first end and the other end as a second end; and a plate stack housed in the internal space of the shell and including a plurality of heat transfer plates (50a, 50b) stacked and joined together, wherein the plate stack is placed so that a stacking direction of the heat transfer plates (50a, 50b) extends in the longitudinal direction of the shell, the shell-and-plate heat exchanger allowing a refrigerant that has flowed into the internal space of the shell to evaporate, wherein a refrigerant outlet for emitting a gas refrigerant out of the internal space is provided at a top of the shell and is arranged near the second end in the longitudinal direction of the shell, the plate stack forms a plurality of refrigerant channels that communicate with the internal space of the shell and allow a refrigerant to flow through and a plurality of heating medium channels that are blocked from the internal space of the shell and allow a heating medium to flow through, each of the refrigerant channels being adjacent to an associated one of the heating medium channels with the heat transfer plate (50a, 50b) interposed therebetween, characterised in that the plate stack is divided into a first heat exchange section and a second heat exchange section each including two or more of the heat transfer plates (50a, 50b), the first and second heat exchange sections (45a, 45b) are arranged in series in a flow path of the heating medium in the plate stack, and the second heat exchange section is arranged downstream of the first heat exchange section in the flow path of the heating medium in the plate stack, and in that each of the first and second heat exchange sections (45a, 45b) is configured to allow a liquid refrigerant in the refrigerant channels to exchange heat with the heating medium flowing through the heating medium channels, to evaporate, the second heat exchange section provides the smallest amount of heat exchange among the first and second heat exchange sections (45a, 45b), and is arranged closest to the refrigerant outlet among the first and second heat exchange sections (45a, 45b), and a number of the heat transfer plates (50a, 50b) in the second heat exchange section is equal to or smaller than a number of the heat transfer plates (50a, 50b) in the first heat exchange section. a shell forming an internal space, wherein the shell is arranged so that its longitudinal direction coincides with a lateral direction, and has one end in the longitudinal direction as a first end and the other end as a second end; and a plate stack housed in the internal space of the shell and including a plurality of heat transfer plates (50a, 50b) stacked and joined together, wherein the plate stack is placed so that a stacking direction of the heat transfer plates (50a, 50b) extends in the longitudinal direction of the shell, the shell-and-plate heat exchanger allowing a refrigerant that has flowed into the internal space of the shell to evaporate, wherein a refrigerant outlet for emitting a gas refrigerant out of the internal space is provided at a top of the shell and is arranged near the second end in the longitudinal direction of the shell, the plate stack forms a plurality of refrigerant channels that communicate with the internal space of the shell and allow a refrigerant to flow through and a plurality of heating medium channels that are blocked from the internal space of the shell and allow a heating medium to flow through, each of the refrigerant channels being adjacent to an associated one of the heating medium channels with the heat transfer plate (50a, 50b) interposed therebetween, characterised in that the plate stack is divided into a first heat exchange section and a second heat exchange section each including two or more of the heat transfer plates (50a, 50b), the first and second heat exchange sections (45a, 45b) are arranged in series in a flow path of the heating medium in the plate stack, and the second heat exchange section is arranged downstream of the first heat exchange section in the flow path of the heating medium in the plate stack, and in that each of the first and second heat exchange sections (45a, 45b) is configured to allow a liquid refrigerant in the refrigerant channels to exchange heat with the heating medium flowing through the heating medium channels, to evaporate, the second heat exchange section provides the smallest amount of heat exchange among the first and second heat exchange sections (45a, 45b), and is arranged closest to the refrigerant outlet among the first and second heat exchange sections (45a, 45b), and a number of the heat transfer plates (50a, 50b) in the second heat exchange section is equal to or smaller than a number of the heat transfer plates (50a, 50b) in the first heat exchange section.