To provide instrument holders in which instruments for assistance can be arranged as close as possible to a patient and can be arranged so as to be divided into small number of pieces, e.g., one or two.

Dental instrument holders include: connectors 20 fixed or freely removably arranged in the desired positions of a dental treatment unit; and the instrument holders 101, 102, etc., to be freely removably connected to the connectors 20. The instrument holders 101, 102 include instrument suspending holes 12 for suspending the one or two instruments.