An ultrasonic diagnostic apparatus comprising: an ultrasonic probe configured to transmit an ultrasound signal to an object and receive a response signal reflected from the object; a controller configured to: control the ultrasonic probe to transmit a first ultrasound signal and receive a first response signal corresponding to the first ultrasound signal, and control the ultrasonic probe to transmit a second ultrasound signal and receive a second response signal corresponding to the second ultrasound signal, an image generator configured to create an ultrasound image of the object based on the first ultrasound signal and the first response signal; a first adjuster equipped with a fixer to fix the ultrasonic probe to form a constant angle with the object; and a second adjuster configured to adjust an angle of transmission of the first ultrasound signal and the second ultrasound signal, wherein the controller is configured to estimate a position of the ultrasonic probe based on the Doppler effect occurring between the second ultrasound signal and the second response signal, the constant angle formed between the ultrasonic probe and the object and the angle of transmission of the second ultrasound signal adjusted by the second adjuster. an ultrasonic probe configured to transmit an ultrasound signal to an object and receive a response signal reflected from the object; a controller configured to: control the ultrasonic probe to transmit a first ultrasound signal and receive a first response signal corresponding to the first ultrasound signal, and control the ultrasonic probe to transmit a second ultrasound signal and receive a second response signal corresponding to the second ultrasound signal, an image generator configured to create an ultrasound image of the object based on the first ultrasound signal and the first response signal; a first adjuster equipped with a fixer to fix the ultrasonic probe to form a constant angle with the object; and a second adjuster configured to adjust an angle of transmission of the first ultrasound signal and the second ultrasound signal, wherein the controller is configured to estimate a position of the ultrasonic probe based on the Doppler effect occurring between the second ultrasound signal and the second response signal, the constant angle formed between the ultrasonic probe and the object and the angle of transmission of the second ultrasound signal adjusted by the second adjuster. control the ultrasonic probe to transmit a first ultrasound signal and receive a first response signal corresponding to the first ultrasound signal, and control the ultrasonic probe to transmit a second ultrasound signal and receive a second response signal corresponding to the second ultrasound signal, an image generator configured to create an ultrasound image of the object based on the first ultrasound signal and the first response signal; a first adjuster equipped with a fixer to fix the ultrasonic probe to form a constant angle with the object; and a second adjuster configured to adjust an angle of transmission of the first ultrasound signal and the second ultrasound signal, wherein the controller is configured to estimate a position of the ultrasonic probe based on the Doppler effect occurring between the second ultrasound signal and the second response signal, the constant angle formed between the ultrasonic probe and the object and the angle of transmission of the second ultrasound signal adjusted by the second adjuster.