In an optical cable communication network, a plurality of optical fibers in an external optical cable are respectively connected to separate optical fibers of respective users through optical fibers to form a communication network. As a device for connecting two optical fibers, the Fiber Optic Splice Closure is widely used in the optical fiber communication network. It is suitable for the installation environment of overhead, pipeline and direct burial of various structural optical cables. It can be effectively waterproof, flame retardant and anti-collision. The cable is stretched and twisted to provide excellent protection and to ensure excellent communication quality in harsh natural environments. Conventional fiber optic splice closures generally include a box body, a cover body, and a splicing tray. Wherein the cover is pivotally connected to the case to open and close the case; the connection tray is pivotally connected to the case, and can be stored in the storage position in the case and abut on the cover Turn between the open positions. A plurality of fiber fusion splicing devices can be installed on the splicing tray for connecting the optical fiber from the optical cable to the branch fiber (also referred to as a pigtail), and the branch fiber is further connected to the user fiber to implement fiber-to-the-home. Branched fibers generally have a certain length. These branch fibers are placed in the fiber optic splice closure, which occupies the internal space of the fiber optic splice closure and is difficult to manage the fiber. A novel optical fiber connection box comprises: a box body, wherein the box body is provided with a through hole for the branch fiber to pass from the outer surface of the box to the inside of the box body; the optical fiber splicing device is mounted on the outer surface of the box body, And configured to connect the branch fiber and the user fiber entering the user end; a cover pivotally connected to the case to open and close the case; and a connection tray pivotally connected to The casing is configured to connect a plurality of optical fibers in the optical cable to the branch optical fibers. The technical problem to be solved by the present invention is to provide a fiber optic splice closure, and a receiving groove for accommodating the branch fiber is disposed inside the box body, so that the branch fiber is neatly arranged in the fiber optic splice closure.