To improve the sliding rotation of a pin in pin holding hole.

This is a manufacturing method for a pin holding ring wherein an internal gear is comprised of this pin holding ring with a semicircular pin holding hole in an inner periphery and a pin rotatably fitted in each pin holding hole, and an external gear is inscribably engaged with this internal gear, forming an inscribed intermeshing gear mechanism, and before an inside diameter DA of a pin holding ring base material 151 is machined up to a finished diameter, a pin holding hole 113a is machined as the whole round hole to the ring base material and, after an inner surface of this pin holding hole 113a is surface- finished by means of roller burnishing machining, the inside diameter of the pin holding ring is extendedly machined up to the finished diameter, thereby securing this pin holding ring with the semicircular pin holding hole. Doing like this, an interval between the pin holding hole and the pin can be lubricated in a state of being approximated to fluid lubrication.