An article pickup apparatus configured so as to measure surface positions of articles randomly piled on the three-dimensional space using a three-dimensional measurement instrument to acquire position information of three-dimensional points, determine a connected set made by connecting three-dimensional points present in the vicinity of each other among the three-dimensional points, and identify a position and posture of an article based on the position information of three-dimensional points belonging to the connected set. The posture of the article is identified by calculating a main component direction of the connected set by applying main component analysis to the three-dimensional points belonging to the connected set and identifying the posture of the article based on the main component direction.