The invention discloses a device and a technology for loosening treatment on a tobacco sheet bag. The device comprises a box opening unit (1), a tobacco sheet bag loosening device (2) and a material conveying and mixing unit (3), wherein the box opening unit (1), the tobacco sheet bag loosening device (2) and the material conveying and mixing unit (3) are orderly connected. A rear end of the material conveying and mixing unit (3) is connected to a flue-cured tobacco leaf processing section (4) of a tobacco factory. The box opening unit (1) and the tobacco sheet bag loosening device (2) are parallel to the flue-cured tobacco leaf processing section (4). In the material conveying and mixing unit (3), fully loosened tobacco sheets are uniformly mixed with flue-cured tobacco leaves. The device and the technology can realize automatic, efficient, low-crushing rate and full loosening of a tobacco sheet bag and satisfies technical requirements.