A relay selection method and device for a sidelink, a storage medium and a terminal are provided. The sidelink is a communication link between a first terminal and a second terminal, and the method includes: receiving a first message, wherein the first message includes a first candidate relay set including at least one first candidate relay, quality of a first link between the first terminal and the at least one first candidate relay reaches a preset threshold; selecting a preferred relay from the first candidate relay set based on quality of a second link between the second terminal and the at least one first candidate relay in the first candidate relay set; and determining the preferred relay as a relay of the first terminal and the second terminal on the sidelink.