An ultrasonic diagnostic apparatus comprising: a second communication unit configured to communicate with an ultrasonic probe; a third communication unit configured to communicate with a display apparatus and comprising a port formed on a housing on which the display apparatus is mountable; an image processor configured to generate an ultrasonic image by using a signal received from the ultrasonic probe; and a first controller configured to begin to execute an ultrasonic diagnostic application by which the first controller is configured to change a mode of the display apparatus to an ultrasonic mode through the third communication unit and to activate the ultrasonic probe through the second communication unit, to control the ultrasonic probe through the second communication unit so as to receive an electric signal corresponding to an ultrasonic echo signal from the ultrasonic probe, to control the image processor to generate the ultrasonic image, and to control the display apparatus to display the ultrasonic image through the third communication unit, when the ultrasonic diagnostic apparatus communicates with the ultrasonic probe and the display apparatus, wherein the first controller is configured to provide a notification that only one of the ultrasonic probe and the display apparatus is able to communicate through the display apparatus, when only one of the ultrasonic probe and the display apparatus is able to communicate, and wherein the first controller is configured to generate a notification requesting connection to the ultrasonic probe and to transmit the notification to the display apparatus through the third communication unit so that the display apparatus displays the notification when the ultrasonic diagnostic apparatus is able to communicate with the display apparatus through the third communication unit but is not able to communicate with the ultrasonic probe through the second communication unit. a second communication unit configured to communicate with an ultrasonic probe; a third communication unit configured to communicate with a display apparatus and comprising a port formed on a housing on which the display apparatus is mountable; an image processor configured to generate an ultrasonic image by using a signal received from the ultrasonic probe; and a first controller configured to begin to execute an ultrasonic diagnostic application by which the first controller is configured to change a mode of the display apparatus to an ultrasonic mode through the third communication unit and to activate the ultrasonic probe through the second communication unit, to control the ultrasonic probe through the second communication unit so as to receive an electric signal corresponding to an ultrasonic echo signal from the ultrasonic probe, to control the image processor to generate the ultrasonic image, and to control the display apparatus to display the ultrasonic image through the third communication unit, when the ultrasonic diagnostic apparatus communicates with the ultrasonic probe and the display apparatus, wherein the first controller is configured to provide a notification that only one of the ultrasonic probe and the display apparatus is able to communicate through the display apparatus, when only one of the ultrasonic probe and the display apparatus is able to communicate, and wherein the first controller is configured to generate a notification requesting connection to the ultrasonic probe and to transmit the notification to the display apparatus through the third communication unit so that the display apparatus displays the notification when the ultrasonic diagnostic apparatus is able to communicate with the display apparatus through the third communication unit but is not able to communicate with the ultrasonic probe through the second communication unit.