An endoscope apparatus including an insertion portion to be inserted into a body cavity, and a tip structure constituting a tip portion of the insertion portion. A tip cover is detachably mounted on the tip structure from a side of a tip portion of the tip structure such that the tip cover covers the tip structure. An engagement mechanism is provided on the insertion portion for detachably engaging the tip cover, and a hard finger driven engaging/disengaging member is provided on an outer periphery of a portion of the insertion portion which is located in the vicinity of the engagement mechanism.