The invention is a method for positioning a conveying mechanism having a holding portion for semiconductor wafers. Respective provisional position coordinates of an orienting teaching standard position and a container teaching standard positions are inputted into a controlling unit in advance. A wafer to be conveyed precisely positioned with respect to and held by the holding portion is conveyed and placed on the rotating orienting device according a control based on the provisional coordinates of the orienting teaching standard position. A posture detector then detects the eccentric volume and eccentric direction of the wafer. Appropriate position coordinates are made by amending the provisional coordinates. Then, a wafer to be conveyed precisely positioned with respect to the container teaching standard position is conveyed and placed on the rotating orienting device according a control based on the provisional coordinates of the orienting teaching standard position. A posture detector then detects the eccentric volume and eccentric direction of the wafer. Appropriate position coordinates are made by amending the provisional coordinates.