An apparatus for adjusting a position of the vertebral column of a dummy model for estimating the feeling of sitting in a seat almost exactly mimics the characteristics of the vertebral joints of a human being. The apparatus comprises a pelvic plate; a plurality of lumbar joints, stacked on the pelvic plate so as to be spaced apart from each other, and having joint springs installed in front and rear portions thereof centered around a rotation center interconnecting two adjacent ones thereof; femur joints rotatably installed below the pelvic plate, and connected with one end of each femur bar; and pelvic pivoting members transmitting rotating force of the femur joints, which is caused by vertical pivoting of the femur bars, to the pelvic plate, and changing a vertical angle of the pelvic plate.