1. A microscope apparatus comprising: a microscopic optical system; an imaging section capturing, along an optical axis of the microscopic optical system, a plurality of images at different focal positions, the plurality of images including a cell; a calculating section calculating height information of the cell in a direction of the optical axis of the microscopic optical system based on the different focal positions and a brightness value of pixels in the same position of the plurality of images in the direction of the optical axis, the calculating section finding a focusing position of the cell from a pixel having the maximum or minimum brightness value among the pixels in the same position of the plurality of images, and generating a height of a contour surface of the cell as the height information by using the found focusing position of the cell; and a determining section determining whether the cell is a floating cell or an attached cell based on the height information, the determining section determining a cell having equal or higher contour surface height than a threshold value as the floating cell, and determining a cell having a shorter contour surface height than the threshold value as the attached cell.