A system for determining a position and an attitude of a user terminal, comprising: a position/attitude determination server for receiving position and attitude-related sensor information and camera images that are transmitted from a user terminal operating in conjunction with the position/attitude determination server through a network, wherein the position/attitude determination server comprises: an initial position/attitude determination module for determining initial position information and initial attitude information of the user terminal, based on the sensor information; a database for storing georeferenced reference images in which positions and attitudes of respective cameras, which are obtained at the time of image acquisition via georeferencing, are specified; a search module for searching the database for a georeferenced reference image including an image similar to a received camera image; an image matching module for comparing received camera images with the found georeferenced reference image, and extracting coordinates of image points corresponding to locations of matching images as tie points; a position/attitude adjustment module for, in order to determine final position information and final attitude information of the user terminal corresponding to the tie points with reference to the database, performing a georeferencing procedure based on bundle adjustment on the matching images, and then correcting the initial position information and initial attitude information; and means for feeding the final position information and the final attitude information back to the user terminal. a position/attitude determination server for receiving position and attitude-related sensor information and camera images that are transmitted from a user terminal operating in conjunction with the position/attitude determination server through a network, wherein the position/attitude determination server comprises: an initial position/attitude determination module for determining initial position information and initial attitude information of the user terminal, based on the sensor information; a database for storing georeferenced reference images in which positions and attitudes of respective cameras, which are obtained at the time of image acquisition via georeferencing, are specified; a search module for searching the database for a georeferenced reference image including an image similar to a received camera image; an image matching module for comparing received camera images with the found georeferenced reference image, and extracting coordinates of image points corresponding to locations of matching images as tie points; a position/attitude adjustment module for, in order to determine final position information and final attitude information of the user terminal corresponding to the tie points with reference to the database, performing a georeferencing procedure based on bundle adjustment on the matching images, and then correcting the initial position information and initial attitude information; and means for feeding the final position information and the final attitude information back to the user terminal. an initial position/attitude determination module for determining initial position information and initial attitude information of the user terminal, based on the sensor information; a database for storing georeferenced reference images in which positions and attitudes of respective cameras, which are obtained at the time of image acquisition via georeferencing, are specified; a search module for searching the database for a georeferenced reference image including an image similar to a received camera image; an image matching module for comparing received camera images with the found georeferenced reference image, and extracting coordinates of image points corresponding to locations of matching images as tie points; a position/attitude adjustment module for, in order to determine final position information and final attitude information of the user terminal corresponding to the tie points with reference to the database, performing a georeferencing procedure based on bundle adjustment on the matching images, and then correcting the initial position information and initial attitude information; and means for feeding the final position information and the final attitude information back to the user terminal.