Abstract: Generally stated, the present invention is directed to a liquid light guide for surgical instrumentation, which includes a flexible elongated tube having first and second end portions, first and second light transmissive members disposed at respective first and second end portions of the elongated tube to substantially seal an interior portion of the elongated tube and a light transmissive medium filing the interior portion of the elongated tube. The preferred light transmissive medium comprises a heavy mineral oil having a specific gravity greater than or equal to about 0.86. Preferred light transmissive members are drawn glass rods having polished ends and an index of refraction substantially equal to the transmissive medium. The liquid light guide of the present invention is capable of providing nearly 100% light transmission over the entire visible spectral range while substantially reducing undesired transmission of infrared and ultraviolet radiation.