The invention aims at providing a composite technological outer culvert capable of quickly replacing an outer culvert flow channel. The outer culvert flow channel is divided into a movable flow channel and a fixed flow channel in the navigating direction. The composite technological outer culvert comprises an outer culvert body, the outer culvert body is overall composed of a composite and separated into a front cover and a back cover along the navigating direction separating face perpendicular to the navigating direction, the front cover is used for supplying the fixed flow channel, and the back cover is used for supplying the movable flow channel; the front cover and the back cover are each separated into a left piece and a right piece along the profile parallel to the navigating direction, and the left pieces and the right pieces each comprise a radial inner layer, a radial outer layer and partitioning walls which are connected with the radial inner layer and the radial outer layerand located at the two circumferential ends; and the axial ends, corresponding to the navigating direction separating face, of the left piece of the front cover and the left piece of the back cover are connected in a sealing and butt-joint mode and locked through lock catch mechanisms capable of being tripped, and the axial ends, corresponding to the navigating direction separating face, of the right piece of the front cover and the right piece of the back cover are connected in a sealing and butt-joint mode and locked through lock catch mechanisms capable of being tripped.