To provide a heating-cooling treatment apparatus for a packaging strip, which comes free from troubles due to the twists and tangles of the packaging strip, by carrying it with a moderate tension being kept, in subjecting the packaging strip to a continuous heating-cooling treatment.

The heating-cooling treatment apparatus for a continuous packaging strip 4 includes: treatment devices 2, 3 that house treatment mediums respectively for heating treatment of and cooling treatment of a continuous packaging strip 4 enclosing liquid substance therein; press-for-flattening devices 6, 6 that contain guiding members 5, 5 which impart press-for-flattening effect to the continuous packaging strip 4 while it is kept under tension in the respective treatment devices 2, 3 and is transported spirally or in the state of a character-8 shape, upward and downward in multiple times. A sliding roll 7 is placed, in a bridging manner, at a bridging portion of the packaging strip 4 as is conveyed from the heating treatment device 2 to the cooling treatment device 3, the sliding roll lifting according to the tension-filled or relaxed state of the bridging portion, while either of the press-for-flattening devices 6, 6 is made to increase or decrease its transporting velocity in accordance with the lifting of the sliding roll 7.