A refrigerant evaporator comprising: a plurality of flat tubes disposed along the vertical direction; and a refrigerant distribution and supply section that causes inflowing refrigerant to flow out to the plurality of flat tubes on the downstream side, wherein the refrigerant distribution and supply section includes a refrigerant supply section extending in the vertical direction and in which are formed a plurality of supply spaces (86A to 86L) that divide the plurality of flat tubes into a plurality of refrigerant paths (65A to 65L) including a predetermined number of the flat tubes along the vertical direction and cause the refrigerant to flow out, characterised in that the refrigerant distribution and supply section further includes a refrigerant introduction and distribution section extending in the vertical direction and having a refrigerant introduction section, in which is formed an introduction space for introducing the inflowing refrigerant from a lower end side surface, and a refrigerant distribution section, in which is formed a distribution space for distributing the refrigerant, and a plurality of connecting passages (88Ato 88L) that guide the refrigerant from the refrigerant distribution section to the plurality of supply spaces in the refrigerant supply section, and given that the supply space positioned on the lowermost side out of the plurality of supply spaces is a lowermost-tier supply space, and that the connecting passage that guides the refrigerant to the lowermost-tier supply space out of the plurality of connecting passages is a lowermost-tier connecting passage, and that the flat tube (63A1) positioned on the lowermost side out of the flat tubes communicating with the lowermost-tier supply space is a first flat tube, the first flat tube is disposed in a height position included in a height range of the introduction space, and the lowermost-tier connecting passage is disposed in a position higher than the introduction space. a plurality of flat tubes disposed along the vertical direction; and a refrigerant distribution and supply section that causes inflowing refrigerant to flow out to the plurality of flat tubes on the downstream side, wherein the refrigerant distribution and supply section includes a refrigerant supply section extending in the vertical direction and in which are formed a plurality of supply spaces (86A to 86L) that divide the plurality of flat tubes into a plurality of refrigerant paths (65A to 65L) including a predetermined number of the flat tubes along the vertical direction and cause the refrigerant to flow out, characterised in that the refrigerant distribution and supply section further includes a refrigerant introduction and distribution section extending in the vertical direction and having a refrigerant introduction section, in which is formed an introduction space for introducing the inflowing refrigerant from a lower end side surface, and a refrigerant distribution section, in which is formed a distribution space for distributing the refrigerant, and a plurality of connecting passages (88Ato 88L) that guide the refrigerant from the refrigerant distribution section to the plurality of supply spaces in the refrigerant supply section, and a refrigerant supply section extending in the vertical direction and in which are formed a plurality of supply spaces (86A to 86L) that divide the plurality of flat tubes into a plurality of refrigerant paths (65A to 65L) including a predetermined number of the flat tubes along the vertical direction and cause the refrigerant to flow out, characterised in that the refrigerant distribution and supply section further includes a refrigerant introduction and distribution section extending in the vertical direction and having a refrigerant introduction section, in which is formed an introduction space for introducing the inflowing refrigerant from a lower end side surface, and a refrigerant distribution section, in which is formed a distribution space for distributing the refrigerant, and a plurality of connecting passages (88Ato 88L) that guide the refrigerant from the refrigerant distribution section to the plurality of supply spaces in the refrigerant supply section, and given that the supply space positioned on the lowermost side out of the plurality of supply spaces is a lowermost-tier supply space, and that the connecting passage that guides the refrigerant to the lowermost-tier supply space out of the plurality of connecting passages is a lowermost-tier connecting passage, and that the flat tube (63A1) positioned on the lowermost side out of the flat tubes communicating with the lowermost-tier supply space is a first flat tube, the first flat tube is disposed in a height position included in a height range of the introduction space, and the lowermost-tier connecting passage is disposed in a position higher than the introduction space.