To provide a car washing brush having high washability without damaging a vehicle body and excellent durability and fire-proof property (flame retardancy and spontaneous extinguishing property).

The car washing brush includes filaments made of a polymeric composite material containing a soft vinyl chloride resin as a main component. The cross sectional shape of a washing piece 10 in the car washing brush has a polygonal cross sectional shape, a star cross sectional shape, a shape with projections/recesses in the circumference of the cross section, and a shape with acute parts in the circumference of the cross section.