The present invention features a modular back pack system having a bag with a zippered bag cover located on a bag top. A first adjustable shoulder strap and a second adjustable shoulder strap are located on a bag front. A bottom waist support is located on the bag front close to a bag bottom. The system features attachment straps and a water pouch with a water bag having a drinking hose. The system features a bag extension located in the bag having a flexible channel located around a bag top periphery. A gun pouch is located in the bag bottom. The system features a quiver, a sleeping bag and chair pouch, and a sleeping mat that attaches to the modular back pack system.