An elastomer composition, having an excellent flexibility and low temperature durability, a method for producing the same and a pneumatic tire using the same are provided. An elastomer composition (C) comprising a matrix of a thermoplastic resin (A), in which a dispersed phase of an elastomer component (B) is finely dispersed to form an island-in-sea structure, wherein volume ratios of the thermoplastic resin (A) and the elastomer component (B) satisfy the following formula (I): φd/φm>ηd/ηm  (I) wherein φd and ηd, respectively, indicate a volume ratio and a melt viscosity of the elastomer component (B), and φm and ηm, respectively, indicate a volume ratio and a melt viscosity of the thermoplastic resin (A)), a method for producing the same and a pneumatic tire using the same.