The present invention relates to optical tweezers having a structure for realizing a great object-trapping force. The optical tweezers form an optical trap for trapping an object in, and in the vicinity of, each of plural trapping positions by converging output beams in each of the trapping positions. The optical tweezers comprise light emitting means for outputting a reading light, hologram generating means for generating an output hologram by arranging plural partial holograms two-dimensionally such that each partial hologram causes an output beam to converge in a corresponding trapping position, and a spatial light modulator for generating plural output beams, each of which has been phase-modulated in accordance with the output hologram, from the reading light which reaches the spatial light modulator. In particular, the hologram generating means arrange partial holograms belonging to a group which corresponds to one of the trapping positions such that the partial holograms are divided between two regions obtained by partitioning the output hologram in two, for example.