The invention discloses a riverway artificial eco-island. The riverway artificial eco-island comprises a matrix functional region and an ecological slope protection region. The ecological slope protection region is arranged outside the matrix functional region. The matrix functional region comprises a river sand layer, a first gravel layer, a second gravel layer, a volcanic rock layer and a soil layer from bottom to top. The ecological slope protection region comprises geotechnical cloth, a gridding fence and a silt layer from inside to outside. Aquatic plants are planted on the silt layer andthe soil layer. A water through pipe is arranged in the first gravel layer, and penetrates through the ecological slope protection region to be communicated with external water. In this way, a fixedeco-island form can be formed, water is purified through the physical and chemical effects such as absorption, filtering and microorganism removal of a filler matrix, and losses of filler of the filler matrix is avoided through the ecological slope protection region. Meanwhile water exchange between the interior and the exterior of the eco-island is guaranteed, the interior of the eco-island is not in a completely closed state, and communication between the interior and the exterior of the eco-island is improved.