1. An automatic surveying system, comprising: a surveying device; a collinear-line calculating processor that obtains a collinear line which satisfies a collinear condition for an arbitrarily designated point on a schematic image of which the positional relation to said surveying device is known; a sighting-direction control processor that controls a sighting direction of said surveying device to move along said collinear line; an object point searching processor that searches for an object point, where the position of said object point can be determined as a point on said collinear line by measuring said sighting direction with said surveying device while carrying out the sighting direction control process; and wherein a position obtained by said object point searching processor coincides with an object point that corresponds to said designated point on said schematic image.