| abstract |
A process for producing a conjugated diene polymer in which a conjugated diene polymer with narrow molecular weight distribution and high cis-bond content can be easily produced at low cost. This process comprises the polymerization step of polymerizing a conjugated diene compound with the use of a catalyst composition containing a rare earth element-containing compound or a reaction product of the compound with a Lewis base, aluminoxane and/or an organoaluminum compound and an iodine-containing compound to thereby obtain a conjugated diene polymer having a cis-1, 4-bond content of 98.5 mass% or higher and a ratio (Mw/Mn) of weight average molecular weight (Mw) to number average molecular weight (Mn) of 2.5 or less measured by gel permeation chromatography. |