[Object] To provide an information processing apparatus, an assistance system, and an information processing method that enable suitable assistance to be performed on a surgeon.[Solving Means] An information processing apparatus includes a control unit. The control unit extracts, on the basis of a first image obtained by picking up an image of a surgical part including an affected part and metadata of a situation obtained from past surgery or examination, a parameter of assistance performed with respect to the situation, which is made to correspond to the metadata.