To provide a condenser capable of enhancing cooling performance.

This condenser in provided with heat exchanger tubes 12 arranged in parallel between a pair of headers 11, having both ends thereof connected in communication with the two headers 11 and divided into three paths P1-P3 by partitioning members 16. A refrigerant made to flow in from a refrigerant inlet 11a of a lower part of the header is caused to flow through the paths P1-P3, moves upward in zigzag and is discharged from a refrigerant outlet 11b in a upper part of the header. Cross-sectional areas of the refrigerant flow paths P1-P3 are gradually decreased stepwise toward a downstream side for the respective paths, and reduction ratio of cross-sectional area of the downstream side refrigerant flow path to the upstream side path is set to 20% or more.