the change of the vehicle inertia therefore shift shock may occur there is therefore a need for an apparatus and a method for reducing shift shock that occurs because of the change of the vehicle speed exemplary apparatus and methods will now be described fig4 is a schematic diagram of an automatic transmission to which an upshift control method according to an exemplary embodiment of the present invention is provided the automatic transmission receives torque from an input shaft 30 connected to an engine 10 and transmits the torque to an output shaft 80 in addition at least one planetary gear set is interposed between the input shaft 30 and the output shaft 80 such that a rotation speed of the input shaft 30 is changed into a target rotation speed which is transmitted to the output shaft 80 further at least one frictional element that selectively connects an operational members of the planetary gear set to the input shaft 30 to a transmission case not shown or to another operational member is disposed in the automatic transmission for ease of description only first and second drive gears 40 and 50 first and second driven gears 90 and 100 an on coming element 60 and an off going element.