To provide a down pipe holding device which obtains different mounting finish or appearance by employing a single type of down pipe, and contributes to reduction in the type thereof and the amount of stock, to thereby improve the productivity and workability thereof.

The down pipe holding device is formed of the cylindrical down pipe 1 and the down pipe holder 2 for sheathing and holding the down pipe 1. A one-side portion 3 of the down pipe 1 is formed so as to be different in outer shape from an opposite-side portion 4, and groove portions 5 are formed at boundary portions between the one-side portion 3 and the opposite-side portion 4 in a manner being bent inward in a longitudinal direction. Further, an almost U-shaped down pipe holding portion 6 is formed in the down pipe holder 2, for accommodating the down pipe 1 therein, and the down pipe holding portion 6 has projecting pieces 7 formed at its extreme tips thereof, which protrude inward to engage with the respective groove portions 5.