To keep smooth sliding of a cross roller coupling body and to attain certain operation of a screw device.

A cross roller coupling body 10 has a number of cylindrical rollers 7 and holding members. The holding member is made of PTFE and holds the cylindrical rollers 7 while crossing each other. The holding members are arranged so as to face both ends of the cylindrical rollers 7, and have side plates so as to cover the end surfaces. The presence of the side plates prevents occurrence of skew, and makes the cylindrical rollers 7 smoothly roll. Droppage of the cylindrical rollers 7 is prevented by engaging recessions and projections respectively formed end faces of the cylindrical rollers 7 and the inner surfaces of the side plates.