An endoscope, provided with a raising base, is provided, which can securely lock a guidewire using the raising base.In the raising base, which is provided with a treatment-tool support groove and a pair of raising-base side walls on the left and right sides thereof, a inner-to-outer communicably-connected groove which communicably connects the inner side of the treatment-tool support groove with the outer side thereof is formed in at least one of the pair of raising-base side walls; and when the raising base is positioned at the raised position, the guidewire externally projects through the inner-to-outer communicably-connected groove from the treatment-tool support groove to lock-engage with the raising base.