1. An optical image measuring device comprising: an optical system that splits a light beam from a light source into signal light and reference light, generates interference light by causing said signal light propagated through a fundus oculi of an eye to be examined and said reference light propagated through a reference object to interfere, and generates detection signals by detecting said interference light; and an image forming circuit that forms a tomographic image of said fundus oculi based on said detection signals; said optical image measuring device comprising a first processor, the optical image measuring device further comprising: an alignment part that projects an alignment bright point from a second light source to the eye in order to perform alignment of said optical system with respect to the fundus oculi; a focusing part that focuses said optical system with respect to a region of interest of said fundus oculi; a determining part, comprised by said first processor, that determines the suitability of the position of said optical system after the alignment by said alignment part, the suitability of the focus state after the focusing by said focusing part, and the suitability of the position of the tomographic image of said region of interest in a frame after the tomographic image is formed by said image forming circuit; and a controller, comprising a second processor or comprised by said first processor, that, when it is determined that all of the position of said optical system, the position of said focus state and the position in said frame are appropriate through repeated suitability determination, controls said optical system and said image forming circuit, making it possible to obtain the tomographic image of said region of interest, wherein the determinations of a series of the suitability of the position of said optical system, the suitability of the focus state, and the suitability of the position of the tomographic image of said region of interest are repeated after the determinations are all completed once.