A spun yarn take-up system comprising: spun yarn take-up apparatuses which are lined up in a predetermined direction; a yarn threading robot which is movable in the predetermined direction and is capable of performing yarn threading onto the spun yarn take-up apparatuses; and a compressed fluid supplier configured to supply compressed fluid to the yarn threading robot, wherein, the yarn threading robot includes a sucking retaining unit configured to generate a negative pressure when the compressed fluid is supplied from the compressed fluid supplier and is configured to perform the yarn threading while sucking and retaining a yarn by the sucking retaining unit, a supply passage for supplying the compressed fluid from the compressed fluid supplier to the sucking retaining unit includes: a system-side supply pipe extending from the compressed fluid supplier to the spun yarn take-up apparatuses; a robot-side supply pipe connected to the sucking retaining unit; a system-side supply pipe connecting member attached to a downstream end of the system-side supply pipe; and a robot-side supply pipe connecting member attached to an upstream end of the robot-side supply pipe, and the robot-side supply pipe connecting member and the system-side supply pipe connecting member are arranged to be detachable from each other and attachable to each other, characterized in that the yarn threading robot includes a driving unit which is configured to move the robot-side supply pipe connecting member to be attached to or detached from a system-side supply pipe connecting member. spun yarn take-up apparatuses which are lined up in a predetermined direction; a yarn threading robot which is movable in the predetermined direction and is capable of performing yarn threading onto the spun yarn take-up apparatuses; and a compressed fluid supplier configured to supply compressed fluid to the yarn threading robot, wherein, the yarn threading robot includes a sucking retaining unit configured to generate a negative pressure when the compressed fluid is supplied from the compressed fluid supplier and is configured to perform the yarn threading while sucking and retaining a yarn by the sucking retaining unit, a supply passage for supplying the compressed fluid from the compressed fluid supplier to the sucking retaining unit includes: a system-side supply pipe extending from the compressed fluid supplier to the spun yarn take-up apparatuses; a robot-side supply pipe connected to the sucking retaining unit; a system-side supply pipe connecting member attached to a downstream end of the system-side supply pipe; and a robot-side supply pipe connecting member attached to an upstream end of the robot-side supply pipe, and a system-side supply pipe extending from the compressed fluid supplier to the spun yarn take-up apparatuses; a robot-side supply pipe connected to the sucking retaining unit; a system-side supply pipe connecting member attached to a downstream end of the system-side supply pipe; and a robot-side supply pipe connecting member attached to an upstream end of the robot-side supply pipe, and the robot-side supply pipe connecting member and the system-side supply pipe connecting member are arranged to be detachable from each other and attachable to each other, characterized in that the yarn threading robot includes a driving unit which is configured to move the robot-side supply pipe connecting member to be attached to or detached from a system-side supply pipe connecting member.