Provided is an inspection apparatus or observation apparatus enabling appropriate inspection or observation of a sample in an easy-to-use manner, using a charged-particle technique and an optical technique. Specifically, provided is an inspection or observation apparatus including: a first casing forming at least part of a first space constituting at least part of a region through which a primary charged-particle beam emitted from a charged-particle irradiation section reaches a sample, the first space capable of being maintained in a vacuum state; a second casing provided on the first casing to form at least part of a second space capable of storing the sample therein; a partition wall section for partitioning the first space and the second space from each other, the partition wall section disposed so as to be coaxial with the charged-particle irradiation section when the sample is irradiated with the primary charged-particle beam from the charged-particle irradiation section; and an optical observation section for casting light onto the sample and detecting light from the sample from the same direction as the charged-particle irradiation section.