Preparation of polyisoprene

A method for producing polyisoprene comprising : polymerizing isoprene by using an isoprene-containing composition containing isoprene and an oxygen-containing neutral compound, and a polymerization catalyst composition containing a rare earth element compound and an organometallic compound, wherein : -a compounding amount of the organometallic compound is 0.6 to 3.0 parts by mass per 100 parts by mass of the isoprene-containing composition.