A form measuring apparatus comprising: a probe having a stylus supported by a probe main body and a tip provided to an end of the stylus, the tip being configured to measure a measured object; a driver configured to move the probe; a probe coordinate detector configured to detect coordinates of the probe; a deflection vector detector configured to detect a deflection vector of the probe, a direction of the deflection vector aligning with a direction of a normal line for a surface of the measured object at a point of contact between the measured object and the tip; an angle calculator configured to calculate an angle created between a direction of the deflection vector and a specified direction; a tip coordinate calculator configured to calculate the coordinates of the tip based on the coordinates and the deflection vector of the probe; a controller configured to execute a first scanning control, causing the driver to move the probe such that the tip scans along an inclined surface (61a; 61b) of a V groove to approach a center of the V groove, the controller further configured to execute a second scanning control, causing the driver to move the probe such that the tip scans along the inclined surface (61a; 61b) of the V groove to approach the center of the V groove from a side opposite that of the first scanning control; a threshold value-correspondent coordinate obtainer configured to obtain, as first coordinates, coordinates of the tip where the angle has changed to exceed a first threshold value during execution of the first scanning control, and configured to obtain, as second coordinates, coordinates of the tip where the angle has changed to exceed a second threshold value during execution of the second scanning control; and a V groove center calculator configured to calculate coordinates of the V groove center based on the first coordinates and the second coordinates, the coordinates of the V groove center being an average of the first coordinates and the second coordinates. a probe having a stylus supported by a probe main body and a tip provided to an end of the stylus, the tip being configured to measure a measured object; a driver configured to move the probe; a probe coordinate detector configured to detect coordinates of the probe; a deflection vector detector configured to detect a deflection vector of the probe, a direction of the deflection vector aligning with a direction of a normal line for a surface of the measured object at a point of contact between the measured object and the tip; an angle calculator configured to calculate an angle created between a direction of the deflection vector and a specified direction; a tip coordinate calculator configured to calculate the coordinates of the tip based on the coordinates and the deflection vector of the probe; a controller configured to execute a first scanning control, causing the driver to move the probe such that the tip scans along an inclined surface (61a; 61b) of a V groove to approach a center of the V groove, the controller further configured to execute a second scanning control, causing the driver to move the probe such that the tip scans along the inclined surface (61a; 61b) of the V groove to approach the center of the V groove from a side opposite that of the first scanning control; a threshold value-correspondent coordinate obtainer configured to obtain, as first coordinates, coordinates of the tip where the angle has changed to exceed a first threshold value during execution of the first scanning control, and configured to obtain, as second coordinates, coordinates of the tip where the angle has changed to exceed a second threshold value during execution of the second scanning control; and a V groove center calculator configured to calculate coordinates of the V groove center based on the first coordinates and the second coordinates, the coordinates of the V groove center being an average of the first coordinates and the second coordinates.