In order to solve the problem that an existing multimode fiber exiting spot focusing method cannot rapidly form a batch focus spot on an exit end of a multimode fiber, the invention provides a methodand system for achieving point-by-point focusing of a multimode fiber exiting spot. The method includes online speckle collection and off-line amplitude optimization; the online speckle collection isfor each modulation sub-region of a spatial light modulator, when in an open state, respectively a non-interference speckle image of the multimode fiber exit end is acquired and an interference speckle image when the reference sub-region is in the open state is collected, and traversing and scanning are conducted on all M modulation sub-regions to obtain a 2M speckle image. The offline amplitude optimization is to calculate the binary amplitude modulation state of each test mode corresponding to all the focusing spots by using the intensity information of the corresponding focus position on the 2M speckle image for the preset N focusing spots and form binary amplitude modulation masks to be loaded one by one on the spatial light modulator to achieve point-by-point focusing of the N exitingspots of the multimode fiber.