A cleaning tool for insertion instrument includes: a cleaning cap configured to be attachable to and detachable from a distal end component portion provided on a distal end side of an insertion portion in an endoscope and covered by a tubular cover when the endoscope is used, attachment and detachment of the cleaning cap to and from the distal end component portion being performed in a state where the cover is removed from the distal end component portion; and a cap-side engaging portion provided on the cleaning cap and configured to be engaged with a distal end component portion-side engaging portion provided on an outer peripheral surface, at least a part of which is covered by the cover, of the distal end component portion.