A compression system for an ergonomic backpack is disclosed. The backpack includes a backpack body having a top side, a bottom side, two lateral sides, a body side, an outer side and a pair of shoulder straps. In the embodiment, each shoulder strap is connected at a junction of the top side and the body side, extended along the corresponding lateral side, threaded through the D-ring with a distal end connected to the backpack body at a junction of the outer side and the lateral side. The invention also comprises an optional back panel and an optional back support device, secured to the body side. The back panel and support device may be filled with padding material such as a gel, foam, rubber, fluid or the like. When the user ties the two straps, the backpack is automatically compressed and moves closer to the user's back. The system, operated like a regular two-strap backpack, allows the user to carry heavier loads for a longer period of time with less fatigue.