is an object of the present invention, when used as an agricultural film, without lowering the transparency, to provide a resin composition and agricultural film which exhibits excellent heat retention. The present invention is 100 parts by weight of resin and 1 to 20 resin composition containing the parts by weight of the insulating agent, wherein the insulating agent is of formula (1) as shown, to obtain a molar ratio from 2 of the (110) plane by X-ray diffractometry and a difference of less than 0.7 molar ratio as determined from chemical analysis (a single molar is Mg / Al 2 values of). Mg X Al 2 (OH) 2X + 4 (CO 3 ) mH 2 O (1) (In the formula, X is in the range of 4.0
