A planetary gear train of an automatic transmission for a vehicle may include an input shaft receiving rotary power of an engine, an output shaft outputting the rotary power with rotary speed changed, a first planetary gear set including a first, a second, and a third rotating element, a second planetary gear set including a fourth, a fifth, and a sixth rotating element, a third planetary gear set including a seventh, an eighth, and a ninth rotating element, a fourth planetary gear set including a tenth, an eleventh, and a twelfth rotating element, and six control elements disposed between one of the rotating elements and another or the input shaft, between one of the rotating elements and the output shaft, or between one of the rotating elements and a transmission housing.