Technical characteristics of a new stereoscopic ophthalmic microendoscope system developed for the direct observation of intraocular structures are described herein. Our system includes a stereoscopic visualization mechanism and an image superimposing system that projects the endoscopic image into the eyepiece of the surgical microscope, allowing the surgeon to monitor 3-dimensional endoscopic and microscopic images simply by looking into the eyepiece of the surgical microscope. Stereoscopic visualization of the intraocular structure facilitates fine manipulation of the endoscope probe just above the retina or ciliary body, providing more reliable and safer control of the probe within the eye. Preliminary clinical experience has demonstrated the usefulness of this new system.