PURPOSE: To obtain a tube for heat exchanger capable of suppressing diffusion of a brazing filler metal without causing brazing defect.

CONSTITUTION: The tube constituting cooling medium path is produced with using a clad material 8 cladding a brazing filler metal 7 on one side of a base material 6. The base material 6 uses an aluminum sheet formed to a rectangular shape having a certain width D1. The brazing filler metal 7 with using an aluminum brazing filler metal containing Si is arranged with width D2 shorter than D1 width of the base material 6 so that both ends of the width direction are inside both ends of the base material 6. Accordingly, when a tubular body is formed face to face with both ends of the clad material 8 in the width direction, the prescribed intervals d1, d2 are formed between both ends of the brazing filler metal 7 with peripherally abutting both ends of the base material 6.