A novel ethylene/α-olefin/non-conjugated polyene copolymer comprising structural units derived from ethylene (A), an α-olefin (B) of 3 to 20 carbon atoms, and a non-conjugated polyene (C) containing intramolecularly two or more partial structures in total selected from the group consisting of structures of Formulae (I) and (II), and having a small number of long-chain branches, The novel ethylene/α-olefin/non-conjugated polyene copolymer contains a non-conjugated polyene such as VNB as a copolymerization component and a small long-chain branch content and is excellent in curing properties in the case of crosslinking using peroxide; and a process for producing the ethylene/α-olefin/non-conjugated polyene copolymer, and a use thereof are provided.