PURPOSE: The titled composition, obtained by incorporating a silicone rubber having a specific viscosity with hydrotalcite, single crystal fibers having a high strength, e.g. potassium titanate, and a metal soap, capable of exhibiting sufficient flame retardancy, and having improved nondripping and mechanical characteristics.

CONSTITUTION: A flame-retardant polyolefin composition obtained by incorporating 100pts.wt. polyolefin with 1W10pts.wt., preferably 1W5pts.wt. silicon rubber having 500,000W2,000,000cP viscosity, 10W60pts.wt., preferably 10W30pts.wt. hydrotalcite, 1W20pts.wt., preferably 5W10pts.wt. single crystal fibers having a high strength, about 20μm average fiber length, 0.2W0.3μm average fiber diameter and a diameter and length of 1/50W1/100 those of the conventional glass short fibers and 1W10pts.wt., preferably 3W5pts.wt. metal soap.