A parking assistance apparatus includes a first sensor configured to sense a first environment corresponding to a first distance around a vehicle; a second sensor configured to sense a second environment corresponding to a second distance around the vehicle that is greater than the first distance; and a display configured to display a graphic image. The parking assistance apparatus also includes at least one processor configured to: acquire first information regarding the first environment around the vehicle and second information regarding the second environment around the vehicle; detect an available parking space based on the first information and based on the second information; and based on an available parking space being detected outside of the first environment, control the display to display information regarding the available parking space.