A device having a tube (T) for heating or heat retaining of fluid includes a first path (1) in which a connection section (t) of a cord heater (CH) led out of the tube (T) and a lead wire (LW) connected to a power supply (P) is provided, a second path (2) provided between the tube (T) and the first path (1), and a drainage path for removing leaked fluid of the second path (2). In this device, the connection section (t) is sandwiched by a pair of first sealing members (10, 11) to retain a sealed state and the cord heater (CH) passes through the second path (2) in a sealed state by a second sealing member (20). This device can effectively prevent gas or liquid from leaking into the space where the connection section (t) of a lead wire (LW) and a cord heater (CH) is provided.