An objective of the present invention is to carry out an observation which is easily viewable with a sense of three-dimensionality when observing a wide-angle observation range. Provided is a stereoscopic endoscope optical assembly (1), comprising two objective optical assemblies (2, 3) having optical axes (2a, 3a) which are arrayed with an interval therebetween, and with which the following conditions are satisfied: 0.5mm