Tumor tissue or the like that exists at a deep portion of a living organism far from an internal wall of a body cavity is observed. A biological observation apparatus (1) is provided, which includes an inserted portion (2) that has a small-diameter distal end portion (2a) to be inserted into a body of a specimen (A), such as a mammal or the like, and that emits straight-line laser light (L) in a radial direction from the distal end portion (2a) and an image capturing portion (17) that is disposed outside of the body of the specimen (A) and that captures fluorescence generated from the specimen (A) due to the laser light (L) emitted from the inserted portion (2), wherein the inserted portion (2) is provided with a scanner (8) that scans the laser light (L) in a circumferential direction.
