By using a microfabrication technique such as nanoimprinting, a structure for cell culture comprising: a concavo-convex structure having a plurality of successive unit structures each formed in a polygonal shape in a planar direction and having a minimum internal diameter of less than or equal to 3 μm, wherein a width between adjoining unit structures is less than or equal to 3 μm, a concavo-convex depth is greater than or equal to 10 nm, and the concavo-convex structure functions as a cell adherence surface. By culturing cells in this structure or a cell culture vessel comprising this structure integrated therein, a structure having a spheroid or a vessel having a spheroid, in which a spheroid with lamellipodia has been formed, can be obtained. Thus, it is possible to produce the structure or the cell culture vessel in which the shape, size and material of the peak-and-valley structure are controlled. Furthermore, a spheroid suitable for, e.g., screening a drug can be easily cultured within a short period of time at a low cost.