Apparatus and method for controlling transmission of vehicle

An apparatus of controlling a transmission of a vehicle, the apparatus comprising:

• a determining device configured to determine whether to perform a front-vehicle-based deceleration following control according to information on the vehicle and information on a front vehicle when coasting of the vehicle is started;
• a calculating device configured to determine a target speed of the vehicle and a target distance according to a position of the front vehicle, a speed of the front vehicle, and a moving distance of the front vehicle, when the front-vehicle-based deceleration following control is determined to be performed;
• a gearshifting stage deciding device configured to decide a final gearshifting stage of the transmission according to the determined target speed and the determined target distance by configuring a deceleration profile for each gearshifting stage of the transmission;
• and
• a controller connected to the determining device, the calculating device and the gearshifting stage deciding device and configured to control the transmission according to the final gearshifting stage.