The present invention relates to a real estate brokerage system using a smartphone comprising : a location-based service (LBS) unit for transmitting and receiving cellular location information signals and/or GPS location information signals of a base station; a camera unit interworking with the location-based service unit; and an application software for a real estate sale. The application software comprises : an image database unit for storing real estate image information which is photographed by means of the camera unit interworking with the location-based service unit and having photographing location information tagged or displayed by means of the location-based service unit; a text information database unit for storing text information comprising the surface area, transaction conditions, sale price, offerings characteristics and contact information of real estate corresponding to the photographed real estate image information; an upload unit for uploading online to a remote server the real estate image information and text information which are stored in the image database unit and text information database unit, respectively; a real estate offerings information display unit for searching for or selecting real estate offerings comprising the real estate image information and text information which have been uploaded to the remote server; and a communication connection unit for contacting a real estate seller and a real estate office for the sale of the real estate offerings which have been found or selected. According to the present invention, by means of providing real estate image information, which has photographing location information tagged or displayed by means of the location-based service, for each of whole and specific spaces of real estate offerings, the reliability of the image of the real estate information is assured and the image can be proved to have been photographed at an actual place of the offerings and thus false offerings are prevented and genuineness can be guaranteed.