The invention provides the measuring method for performing monitoring measurement on a plurality of measuring points by using a measuring instrument 1, which comprises a telescope unit for performing sighting of a measuring point where an initial value is already known, a distance measuring unit 29 for measuring a distance to the measuring point by projecting a distance measuring light through the telescope unit, an image sensor 23 for taking an image in direction of measurement and for acquiring a digital image, angle detecting units 31, 32 each for detecting a directional angle in sighting direction of the telescope unit, and an arithmetic unit 27 for making the telescope unit perform automatic sighting to the measuring point and for calculating directional angles of the measuring point based on a deviation of the measuring point on the digital image from a sighting axis and based on a result of detection from the angle detecting unit, wherein the monitoring measurement comprises a coarse monitoring measurement for acquiring a digital image in measuring direction and for performing angle measurement on the measuring point from the digital image, and a precise monitoring measurement for performing sighting of the measuring point by the telescope unit and for performing distance measurement by the distance measuring unit and angle measurement by the angle detecting unit, and wherein the coarse monitoring measurement is executed on each of the measuring points, a deviation of a result of the coarse measurement by the coarse monitoring measurement from the initial value is determined, and the precise monitoring measurement is executed on the measuring point where the deviation exceeds a first threshold value.