To provide a traverse device capable of detecting abnormality of traverse such as loss of synchronism of a traverse guide, thread's twining around winding up drum or the like and of easily judging maintenance timings of each device such as belt, pulley or the like.

In the transverse device 1 performing a transverse movement of thread Y by driving a drive belt body 2 in regular and reverse directions and reciprocating the transverse guide 4 attached on the drive belt body 2, intervals of detecting the transverse guide 4 are measured with a sensor SE1 and it is judged that there is loss of synchronism or deterioration of the transverse device 1 if the intervals exceed a reference value. Then, an origin return control part 20b controls the device to return to the origin S after stopping a drive motor 5. If the number of detection by the sensor SE1 during a certain period of time exceeds a designated value, a third alarm transmitter 18a issues a third alarm to inform necessity of maintenance.