Conjugated diene polymer and conjugated diene polymer composition

A method for manufacturing a conjugated diene polymer comprising a conjugated diene as a monomeric unit, the method comprising:

• a step of producing the conjugated diene polymer by a polymerization reaction in a polymerization solution comprising the conjugated diene, at least one compound selected from the group consisting of limonene, terpinene, and terpinolene, and an organoalkali metal compound as a polymerization initiator,
• Mz/Mn being 1.7 or more and 4.0 or less, when Mz is a Z-average molecular weight of the conjugated diene polymer, Mn is a number average molecular weight of the conjugated diene polymer, and the Z-average molecular weight and the number average molecular weight are values in terms of polystyrene by gel permeation chromatography,
• wherein a Mooney viscosity (ML1+4) of the conjugated diene polymer is 10 or more and 200 or less.