A splicing adhesive film, a manufacturing method thereof, and a photovoltaic module are provided. The splicing adhesive film includes a first portion and a plurality of second portions. The first portion includes a first material, and each second portion includes a second material. The first portion is located in the central region, and the plurality of second portions each are at least partially located in the edge region. The first portion and each second portion are at least partially overlapped in the first direction. The maximum thickness of each second portion located in the edge region is P, and the maximum thickness of the first portion located in the central region is Q, P>Q.