There is provided cell observation apparatus (10) comprising cell observation chamber (30) and optical observation means (70), the cell observation chamber (30) having, disposed thereinside, a pair of wells and a channel through which the wells communicate with each other so that cells of a cell suspension stocked in one of the pair of wells can react with a chemotaxis-factor-containing solution stocked in the other well and can move from the one well to the other well through the channel, the optical observation means (70) capable of optically observing the cells moving through the channel from outside of the cell observation chamber (30), wherein the cell observation chamber (30) with its part exposed from casing (20) is housed in the casing (20) and wherein the optical observation means (70) is housed in the casing (20) so that the optical axis thereof horizontally extends allow in the cell observation chamber (30). Thus, there can be obtained a cell observation apparatus that is compact, being easy in transfer and that has strikingly been improved with respect to handleability.