A method for producing a polyolefin composition, which comprises melt-kneading a particulate composition (A) containing a compound represented by formula (1): wherein R1 represents an alkyl group having 1 to 8 carbon atoms, X represents an n-hydric alcohol residue having 1 to 18 carbon atoms which may include a heteroatom and/or a cyclic group, and n is the integer 2 or 4, and a metal soap, and a particulate polyolefin (B), wherein the ratio (a/b) of the average particle diameter (a) of the particulate composition (A) and the an average particle diameter (b) of the particulate polyolefin (B) is adjusted to 3/1 to 1/3, and wherein average particle diameter means the central cumulative value determined from a weight-based particle diameter cumulative distribution for residue on a sieve measured in accordance with JIS K 0069.