A routing structure between dies is provided, including a trace layer, disposed on a substrate, wherein a plurality of routing paths is embedded in the trace layer. In addition, a first die and a second die are disposed on the trace layer and connected by the routing paths. A spacing gap between the first die and the second die is along a first direction and interfacing edges of the first die and the second die are extending along a second direction perpendicular to the first direction. Each of the routing paths includes a first straight portion in parallel to connect to the interfacing edges. The first straight portion has a slant angle with respect to the first direction other than 0° and 90°.