A substrate and mask aligning apparatus comprising: a stage on which a substrate is loaded on one surface side such that a pad forming surface on which a plurality of pads are formed is directed upward and which is provided to move on a horizontal plane and provided to turn on a same plane; a mask in which through holes are formed in portions corresponding to pads on the substrate that is loaded on the stage; a connecting/disconnecting mechanism for connecting/ disconnecting at least one of the substrate or the mask to/from the other; a shooting section (40, 42) for shooting a superposed state of the through holes of the mask on the pads of the substrate in a state where the mask is brought into contact with the pad forming surface of the substrate loaded on the stage; and a controlling portion for calculating stage moving data which includes a moving direction and an amount of movement of the stage, on the basis of image data picked up by the shooting section (40, 42) to eliminate a difference between a present superposed state of the through holes of the mask, which comes into contact with the pad forming surface of the substrate loaded on the stage, on the pads of the substrate and a scheduled superposed state, and executing repeatedly an operation to move the stage on the basis of calculated moving data of the stage, characterized in that the controlling portion is configured to calculate first moving data necessary for first alignment between positions of the through holes of the mask and the pad forming surface of the substrate on the basis of both the image data of the sole substrate obtained by shooting the pad forming surface in a state where the substrate is loaded on the stage and the image data of the sole mask obtained by shooting a plane state of the sole mask where no tension is applied to the mask, and wherein the controlling portion is further configured to calculate corrected moving data by using data obtained in a superposed state of the mask and the substrate where tension is applied to the mask. a stage on which a substrate is loaded on one surface side such that a pad forming surface on which a plurality of pads are formed is directed upward and which is provided to move on a horizontal plane and provided to turn on a same plane; a mask in which through holes are formed in portions corresponding to pads on the substrate that is loaded on the stage; a connecting/disconnecting mechanism for connecting/ disconnecting at least one of the substrate or the mask to/from the other; a shooting section (40, 42) for shooting a superposed state of the through holes of the mask on the pads of the substrate in a state where the mask is brought into contact with the pad forming surface of the substrate loaded on the stage; and a controlling portion for calculating stage moving data which includes a moving direction and an amount of movement of the stage, on the basis of image data picked up by the shooting section (40, 42) to eliminate a difference between a present superposed state of the through holes of the mask, which comes into contact with the pad forming surface of the substrate loaded on the stage, on the pads of the substrate and a scheduled superposed state, and executing repeatedly an operation to move the stage on the basis of calculated moving data of the stage,