An insertion apparatus includes an inserting section (112) that is to be inserted into an insertion target (P), main body (102) as a reference unit that is disposed outside the insertion target (P), a connection cable (108) that includes a movable section configured to move continuously and connects the inserting section (112) and the main body(102), and a first shape sensor (204) that detects a shape of the cable with respect to the main body (102) by detecting a movable amount of the connection cable (108).
