A planetary gear train of an automatic transmission for a vehicle may include an input shaft receiving power from an engine, an output shaft outputting power changed in speed, a first planetary gear set which has first, second, and third rotating elements, a second planetary gear set which has fourth, fifth, and sixth rotating elements, a third planetary gear set which has seventh, eighth, and ninth rotating elements, a fourth planetary gear set which has tenth, eleventh, and twelfth rotating elements, and six control elements disposed between the rotating elements, and disposed at positions where the rotating elements are selectively connected to a transmission housing.