To realize a grid-pattern projection phase shift measurement which carries out continuous movements and covers a large area.

A surface profile measuring apparatus is provided, which comprises: a grid-pattern projection means 1 for projecting a grid pattern; a photographing means 4; and an X-axis direct acting table 9 for continuously moving an object along one-axis direction. The view field of the photographing means 4 is divided into N parts along a movement axis direction, and images are acquired exactly at respective timings when moving by 1/N part of the view field. As a result, although a certain 1/N part area of the view field is photographed N times in continuous N view field parts, phases of the grid pattern are shifted through respective N images, thereby enabling a phase shift calculation to be carried out.

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