An object of the present invention is to provide a urethane composition for a coating film waterproof material which does not contain any of specific chemical substances, has work efficiency that is the same as that of a general-purpose highly extensible urethane coating film waterproof material, an elongation rate of a highly extensible urethane coating film waterproof material, and strength of a high-strength urethane coating film waterproof material, has no decrease in weather resistance of a top coat resulting from a plasticizer, and is suitable for a non-bleeding type of coating by hand that is not affected by migration of a low fraction of asphalt. The present invention provides a urethane composition for a coating film waterproof material containing at least a primary material (A) containing an isophorone diisocyanate prepolymer generated by reacting polypropylene glycol which has two or more hydroxyl groups and whose hydroxyl group equivalent is 1,500 or more and short-chain polyhydric alcohol with isophorone diisocyanate and a curing material (B) containing diethyl toluene diamine, water, polypropylene glycol that has 1,500 or more hydroxyl group equivalents containing two or more hydroxyl groups, and a terminal-esterified polyfunctional polyether-based or polyoxyalkylene monoalkyl ether acetate ester-based plasticizer.