Method for indoor localization of a user equipped with a localization device having electromagnetic signal receiving means and means for detecting the orientation in a predetermined spatial reference system, wherein said indoor space (2; 3) is divided up into a plurality of rooms each of which includes a plurality of spatial volumes or areas, which are connected together in a directed-graph arrangement, the method including the arrangement of a plurality of radio transmitters designed to each emit a respective localization signal adapted to be detected by said receiver means; said method comprising in combination the following steps: - detection by the receiver means of the localization signals emitted by a plurality of first radio transmitters; - comparison of the power of the localization signals detected with a predetermined threshold value and localization of the device in the spatial volume or area associated with the radio transmitter, the localization signal of which is detected as having a power higher than said threshold value; - should localization signals with a power higher than said threshold value not be detected, determination of a movement condition of the localization device, so that - if the localization device is static: determination of the room in said closed space (2; 3) where said localization device is present based on the power of the localization signals detected by the receiver means; acquisition of a localization vector of said receiver means, the localization vector including the localization signals received from second radio transmitters associated with said room and orientation data of the localization device in the space (2; 3); comparison of said localization vector with a set of localization vectors predetermined during a training step and determination of the localization in the spatial volume or area associated with the localization vector closest to the localization vector acquired, or - if the localization device is moving: tracking the localization device by inertial navigation. - detection by the receiver means of the localization signals emitted by a plurality of first radio transmitters; - comparison of the power of the localization signals detected with a predetermined threshold value and localization of the device in the spatial volume or area associated with the radio transmitter, the localization signal of which is detected as having a power higher than said threshold value; - should localization signals with a power higher than said threshold value not be detected, determination of a movement condition of the localization device, so that - if the localization device is static: determination of the room in said closed space (2; 3) where said localization device is present based on the power of the localization signals detected by the receiver means; acquisition of a localization vector of said receiver means, the localization vector including the localization signals received from second radio transmitters associated with said room and orientation data of the localization device in the space (2; 3); comparison of said localization vector with a set of localization vectors predetermined during a training step and determination of the localization in the spatial volume or area associated with the localization vector closest to the localization vector acquired, or determination of the room in said closed space (2; 3) where said localization device is present based on the power of the localization signals detected by the receiver means; acquisition of a localization vector of said receiver means, the localization vector including the localization signals received from second radio transmitters associated with said room and orientation data of the localization device in the space (2; 3); comparison of said localization vector with a set of localization vectors predetermined during a training step and determination of the localization in the spatial volume or area associated with the localization vector closest to the localization vector acquired, or - if the localization device is moving: tracking the localization device by inertial navigation. tracking the localization device by inertial navigation.