Rotatable, oblique-viewing stereoendoscope comprising: a dual-pupil aperture divided to a first pupil and a second pupil, said first pupil being configured to receive a first image of an object, said second pupil being configured to receive a second image of an object; a proximal objective assembly positioned proximally to said dual-pupil aperture, said proximal objective assembly being configured to focus said first image and said second image; a first image sensor configured to detect said first image focused by said proximal objective assembly, and a second image sensor configured to detect said second image focused by said proximal objective assembly; a relay system positioned distally to said dual-pupil aperture, said relay system being configured to transmit said first image and said second image toward said dual-pupil aperture; and a front optical system positioned distally to said relay system, said front optical system being further configured to produce said first image from said reflected light received through said image of said first pupil and to produce said second image from said reflected light received through said image of said second pupil, characterized in said stereoendoscope further comprising a folding prism, said folding prism being configured to receive reflected light reflected from said object and to direct said reflected light at an oblique angle toward said front optical system, and said front optical system further comprising: a first channel lens assembly, comprising a first lens and a second lens, for reimaging a first pupil of said dual-pupil aperture as a first reimaged pupil distal to said front optical system; and a second channel lens assembly, comprising a first lens and a second lens, for reimaging a second pupil of said dual-pupil aperture as a second reimaged pupil distal to said front optical system, wherein said folding prism is rotatable with respect to said dual-pupil aperture such that a direction of view of said stereoendoscope can be rotated about a longitudinal axis of said relay system; wherein said front optical system reimages said dual-pupil aperture at a distal end immediately proximal to said folding prism; wherein said first channel lens assembly and said second channel lens assembly together form a positive power lenses assembly; and wherein said first reimaged pupil, said second reimaged pupil and said positive power lenses assembly enable a wide field-of-view of said stereoendoscope. a dual-pupil aperture divided to a first pupil and a second pupil, said first pupil being configured to receive a first image of an object, said second pupil being configured to receive a second image of an object; a proximal objective assembly positioned proximally to said dual-pupil aperture, said proximal objective assembly being configured to focus said first image and said second image; a first image sensor configured to detect said first image focused by said proximal objective assembly, and a second image sensor configured to detect said second image focused by said proximal objective assembly; a relay system positioned distally to said dual-pupil aperture, said relay system being configured to transmit said first image and said second image toward said dual-pupil aperture; and a front optical system positioned distally to said relay system, said front optical system being further configured to produce said first image from said reflected light received through said image of said first pupil and to produce said second image from said reflected light received through said image of said second pupil, characterized in said stereoendoscope further comprising a folding prism, said folding prism being configured to receive reflected light reflected from said object and to direct said reflected light at an oblique angle toward said front optical system, and said front optical system further comprising: a first channel lens assembly, comprising a first lens and a second lens, for reimaging a first pupil of said dual-pupil aperture as a first reimaged pupil distal to said front optical system; and a second channel lens assembly, comprising a first lens and a second lens, for reimaging a second pupil of said dual-pupil aperture as a second reimaged pupil distal to said front optical system, a first channel lens assembly, comprising a first lens and a second lens, for reimaging a first pupil of said dual-pupil aperture as a first reimaged pupil distal to said front optical system; and a second channel lens assembly, comprising a first lens and a second lens, for reimaging a second pupil of said dual-pupil aperture as a second reimaged pupil distal to said front optical system, wherein said folding prism is rotatable with respect to said dual-pupil aperture such that a direction of view of said stereoendoscope can be rotated about a longitudinal axis of said relay system; wherein said front optical system reimages said dual-pupil aperture at a distal end immediately proximal to said folding prism; wherein said first channel lens assembly and said second channel lens assembly together form a positive power lenses assembly; and wherein said first reimaged pupil, said second reimaged pupil and said positive power lenses assembly enable a wide field-of-view of said stereoendoscope.