An insertion system having a processor including hardware, configured to: determine, for each of a plurality of times, one or more positions of an insertion section configured to be inserted into an insertion subject； determine, for the each of the plurality of times, state of the insertion section relative to the insertion subject based on the one or more positions for the each of the plurality of times； determine, for the each of the plurality of times, whether an attention state of the insertion section that restricts insertion of the insertion section into the insertion subject has occurred, based on the state of the insertion section relative to the insertion subject determined； and control a monitor to display attention state information indicating the one or more positions of the insertion section at which the occurrence of the attention state of the insertion section is determined over the plurality of times.
