Leporinus sidlauskasi is a species of freshwater ray-finned fish belonging to the family Anostomidae, the toothed headstanders. It is found in the lower Tocantins River in Pará State, Brazil.
It is named in honor of (b. 1976), the Curator of Fishes at Oregon State University, for his contributions to the knowledge of the systematics of the family Anostomidae.