A surgical tool holding device that holds a plurality of surgical tools includes: a flexible insertion section having a distal end and a proximal end and configured such that a surgical tool channel into which the plurality of surgical tools are inserted is formed a driving section configured to advance and retract each of the plurality of surgical tools inside the surgical tool channel an operating section configured to manipulate the plurality of surgical tools and a controller configured to control an amount of protrusion of the surgical tool protruding from a distal end of the surgical tool channel, from the surgical tool channel.
