Method of manufacturing a highly integrated infused box made of composite material with two skins, several ribs, several stringers, a front spar and a rear spar, comprising a first semibox and a second semibox joined by connecting means, such that: - the first semibox comprises one skin and the ribs, and - the second semibox comprises one skin, the front spar, the rear spar and the stringers, characterized in that it comprises the following steps: - Preparation of tool for injection process and dry ATL (Automated Tape Laying) of ribs, skins and stringers: ∘ Tool cleaning. ∘ Applying demoulding means to the tool. - Lay-up: the skins, stringers, spars and ribs are laminated with dry fibre with binder between the plies. - Forming process of spars, ribs and stringers: stringers are formed with a H form and are later cut into two T shapes, and spars and ribs are formed with a J shape. - Manufacturing process of the first semibox, comprising the following sub-steps: ∘ Placing the skin on the base tool. ∘ Placing the ribs over the skin. ∘ Placing rigid rib web tooling modules between the ribs, so that the face of each rib web that does not contain the upper flange of the rib is in contact with one of the sides of the tooling, and the whole is covered with a vacuum bag. ∘ Infusion of the first semibox with resin using LRI (Liquid Resin Infusion) technology. ∘ Curing with auto-heating tools or inside an oven. ∘ Demoulding: once the curing process has finished, the vacuum bag is removed and the tooling (7, 8) is demoulded. ∘ Ultrasonic and dimensional inspection. - Manufacturing process of the second semibox, comprising the following sub-steps: ∘ Placing the skin on the base tool. ∘ Placing the stringers and the spars over the skin. ∘ Placing stringer web flexible tooling modules with resin inlet on the stringers. ∘ Placing rigid spar web tooling modules between the spars, on the skin and on the stringer web flexible tooling modules. ∘ Infusion of the second semibox with resin using LRI (Liquid Resin Infusion) technology. ∘ Curing with auto-heating tools or inside an oven. ∘ Demoulding: once the curing process has finished, the vacuum bag is removed and the tooling (9, 10) is demoulded. ∘ Ultrasonic and dimensional inspection. - Assembly process of the first semibox with the second semibox by means of the drilling and riveting of the joints. - the first semibox comprises one skin and the ribs, and - the second semibox comprises one skin, the front spar, the rear spar and the stringers, - Preparation of tool for injection process and dry ATL (Automated Tape Laying) of ribs, skins and stringers: ∘ Tool cleaning. ∘ Applying demoulding means to the tool. ∘ Tool cleaning. ∘ Applying demoulding means to the tool. - Lay-up: the skins, stringers, spars and ribs are laminated with dry fibre with binder between the plies. - Forming process of spars, ribs and stringers: stringers are formed with a H form and are later cut into two T shapes, and spars and ribs are formed with a J shape. - Manufacturing process of the first semibox, comprising the following sub-steps: ∘ Placing the skin on the base tool. ∘ Placing the ribs over the skin. ∘ Placing rigid rib web tooling modules between the ribs, so that the face of each rib web that does not contain the upper flange of the rib is in contact with one of the sides of the tooling, and the whole is covered with a vacuum bag. ∘ Infusion of the first semibox with resin using LRI (Liquid Resin Infusion) technology. ∘ Curing with auto-heating tools or inside an oven. ∘ Demoulding: once the curing process has finished, the vacuum bag is removed and the tooling (7, 8) is demoulded. ∘ Ultrasonic and dimensional inspection. ∘ Placing the skin on the base tool. ∘ Placing the ribs over the skin. ∘ Placing rigid rib web tooling modules between the ribs, so that the face of each rib web that does not contain the upper flange of the rib is in contact with one of the sides of the tooling, and the whole is covered with a vacuum bag. ∘ Infusion of the first semibox with resin using LRI (Liquid Resin Infusion) technology. ∘ Curing with auto-heating tools or inside an oven. ∘ Demoulding: once the curing process has finished, the vacuum bag is removed and the tooling (7, 8) is demoulded. ∘ Ultrasonic and dimensional inspection. - Manufacturing process of the second semibox, comprising the following sub-steps: ∘ Placing the skin on the base tool. ∘ Placing the stringers and the spars over the skin. ∘ Placing stringer web flexible tooling modules with resin inlet on the stringers. ∘ Placing rigid spar web tooling modules between the spars, on the skin and on the stringer web flexible tooling modules. ∘ Infusion of the second semibox with resin using LRI (Liquid Resin Infusion) technology. ∘ Curing with auto-heating tools or inside an oven. ∘ Demoulding: once the curing process has finished, the vacuum bag is removed and the tooling (9, 10) is demoulded. ∘ Ultrasonic and dimensional inspection. ∘ Placing the skin on the base tool. ∘ Placing the stringers and the spars over the skin. ∘ Placing stringer web flexible tooling modules with resin inlet on the stringers. ∘ Placing rigid spar web tooling modules between the spars, on the skin and on the stringer web flexible tooling modules. ∘ Infusion of the second semibox with resin using LRI (Liquid Resin Infusion) technology. ∘ Curing with auto-heating tools or inside an oven. ∘ Demoulding: once the curing process has finished, the vacuum bag is removed and the tooling (9, 10) is demoulded. ∘ Ultrasonic and dimensional inspection. - Assembly process of the first semibox with the second semibox by means of the drilling and riveting of the joints.