To provide an instrument holder with a high degree of freedom in 5-axis movement since conventionally fixation or turning movement to the left and right and 3-axis movement of angle inclination are performed to a bracket table above for the posture control of the instrument holder integrated with the bracket table of a dental chair unit but a range is limited and the degree of freedom is low.

The dental instrument holder is provided with a first horizontal direction rotary shaft of the instrument holder fixed to the lower surface front part of the bracket table above, a first vertical direction rotary shaft disposed below it, a second horizontal direction rotary shaft attached to the back surface lower part of the holder, and a second vertical direction rotary shaft disposed above it. The first vertical direction rotary shaft and the second vertical direction rotary shaft are pivoted by an arm, the second horizontal direction rotary shaft of the holder and the second vertical direction rotary shaft disposed above it are connected to a horizontal inclination angle adjusting mechanism for adjusting the inclination angle at the front and back of the instrument holder, and the joint part of the total of five shafts which are two shafts in a horizontal direction, two shafts in a vertical direction, and one shaft in an inclined direction is provided.