To provide a structure for installing a pipe to a tank which does not require joining such as brazing or welding of pipe used for feeding oil to or sucking it from a tank.

In a structure 10 for installing a pipe to a tank 12, the tank 12 has an opening 12a on its wall surface, and a tubular connecting portion 14 surrounding the periphery of the opening 12a and extending outward. A rigid tube member 16 extending from outside to inside of the tank 12 is inserted into the tubular connecting portion 14. Furthermore, an elastic tube member 18 covers the outer periphery of the tubular connecting portion 14 and the rigid tube member 16. The elastic tube member 18 creates tightening force to contract on the outer periphery of both tubular connecting portion 14 and rigid tube member 16, which are therefore retained and connected.