The primary object of the invention is an arrangement in the fibrous-web machine for tail-threading of a fibrous web, a tail-threading apparatus and a method for tail-threading. The arrangement comprises a tail-threading apparatus which is arranged to receive a tail separated from the fibrous web and to guide it further to the subsequent section of the fibrous-web machine in the longitudinal direction of the fibrous-web machine, at least one blower (102, 104) which is provided with a flow-preventing plate (103, 105) and arranged to guide the tail towards said tail-threading apparatus for feeding the tail to the tail-threading apparatus, whereby said at least one blower (102, 104) with its flow-preventing plate (103, 105) is arranged to divert the travel direction of tail on the longitudinal vertical plane and the cross-directional vertical plane of the fibrous-web machine, and said tail-threading apparatus comprises a rope nip receiving the tail the tail-threading ropes of which are supported by a rope pulley (108) which is arranged to rotate on a plane in the direction of the longitudinal axis of the fibrous-web machine and oblique in relation to the vertical direction and which is arranged to receive the diverted tail in the diverted travel direction. The invention enables the implementation of a tail-threading process fitting into a smaller space.