A distributor (100, 109, 110) configured to distribute refrigerant to each of a plurality of heat transfer tubes extending in an up-down direction, the plurality of heat transfer tubes being spaced apart from each other in a first direction crossing the up-down direction, the distributor comprising: a first member having a plurality of first through holes spaced apart from each other in the first direction; a second member having a first groove facing each of the plurality of first through holes; and a third member having at least one second groove provided to face at least one of the plurality of first through holes, wherein the first groove extends in the first direction, a first space inside the first groove and a second space inside the at least one second groove are connected to each other through a third space inside each of the plurality of first through holes, and an inner diameter of the at least one second groove in the second direction is longer than the length of the opening end of the first groove in a second direction crossing the up-down direction and the first direction, a length of an opening end of the first groove in the second direction is longer than an inner diameter of each of the plurality of the first through holes in the second direction, characterised in that the second member is configured as an outer member of the distributor (100, 109, 110) and has an upper surface (100A, 109A, 110A) of the distributor (100, 109, 110), the outer member being disposed above the third member and facing at least a part of the at least one second groove, wherein the upper surface (100A, 109A, 110A) of the outer member is provided with a plurality of third through holes facing the at least one second groove, the plurality of third through holes being spaced apart from each other in the first direction, and each of the plurality of third through holes has a long-side direction extending in the second direction; and wherein the third space is disposed on the same side of the second space as each of the plurality of third through holes. a first member having a plurality of first through holes spaced apart from each other in the first direction; a second member having a first groove facing each of the plurality of first through holes; and a third member having at least one second groove provided to face at least one of the plurality of first through holes, wherein the first groove extends in the first direction, a first space inside the first groove and a second space inside the at least one second groove are connected to each other through a third space inside each of the plurality of first through holes, and an inner diameter of the at least one second groove in the second direction is longer than the length of the opening end of the first groove in a second direction crossing the up-down direction and the first direction, a length of an opening end of the first groove in the second direction is longer than an inner diameter of each of the plurality of the first through holes in the second direction, characterised in that the second member is configured as an outer member of the distributor (100, 109, 110) and has an upper surface (100A, 109A, 110A) of the distributor (100, 109, 110), the outer member being disposed above the third member and facing at least a part of the at least one second groove, wherein the upper surface (100A, 109A, 110A) of the outer member is provided with a plurality of third through holes facing the at least one second groove, the plurality of third through holes being spaced apart from each other in the first direction, and each of the plurality of third through holes has a long-side direction extending in the second direction; and the upper surface (100A, 109A, 110A) of the outer member is provided with a plurality of third through holes facing the at least one second groove, the plurality of third through holes being spaced apart from each other in the first direction, and each of the plurality of third through holes has a long-side direction extending in the second direction; and wherein the third space is disposed on the same side of the second space as each of the plurality of third through holes.