A medical instrument holding apparatus includes a supporting mechanism having an extension which includes a bore, a medical instrument, and an attachment device includes a shaft slidably engaged in the bore of the extension, and the shaft includes one end portion secured to the medical instrument, and the attachment device includes a handle provided on the shaft, and the shaft is adjustable relative to the extension of the supporting mechanism to a selected position. The extension includes a slot communicating with the bore of the extension for forming two separated flaps, and includes a fastener engaged with the flaps for forcing the flaps to engage with the shaft and to detachably and adjustably secure the shaft to the extension of the supporting mechanism.
