PROBLEM TO BE SOLVED: To provide an X-ray computer tomographic apparatus capable of reducing an impact caused by the deterioration of a degree of precision in the horizontal movement of a top board included in a bed device.SOLUTION: A bed device includes a top board for placing an object to be examined. First operation condition acquisition means acquires a first operation condition including a first velocity to move the top board. First control means moves the top board on the basis of the first velocity included in the acquired first operation condition. Velocity acquisition means acquires the velocity of the top board moved by the first control means. Calculation means calculates a velocity error between the first velocity included in the acquired first operation condition and the acquired velocity of the top board. Second operation condition acquisition means acquires a second operation condition including a second velocity to move the top board. Second control means moves the top board on the basis of the second velocity included in the acquired second operation condition and the calculated velocity error.
