1. An imaging apparatus having an imaging unit, comprising: a registration unit configured to register a plurality of feature data up to an upper limit number in a nonvolatile memory in association with a same object; an authentication unit configured to identify whether an object detected from an image captured by the imaging unit is a registered object based on the feature data registered in the nonvolatile memory; a selection unit configured to select one of objects registered in the nonvolatile memory for which new feature data is registered by the registration unit; and a control unit configured to perform control to display a selection screen for allowing, when the object selected by the selection unit is the object for which the upper limit number of feature data has been registered, a user to select the feature data to be replaced with the new feature data among the upper limit number of feature data registered for the object; wherein the registration unit registers the new feature data by replacing the feature data selected on the selection screen.