Abstract: Aqueous emulsions of olefin polymers and bitumen comprise:(a) 5-30% by weight of an extensively amorphous poly-.alpha.-olefin or poly-.alpha.-olefin mixture having viscosity numbers J of 5-400 cc./g. and ether-soluble proportions of more than 60%, wherein up to three quarters by weight of these polyolefins can be replaced by an elastomer;(b) 5-40% by weight of a hydrocarbon oil optionally containing a drying oil, wherein the hydrocarbon oil is a polybutene oil or the distillation residue form cyclododecatriene manufacture and/or a mixture of both;(c) 10-40% by weight of a bitumen;(d) 0-10% by weight of a chlorinated paraffin having a chlorine content of 45-60% and/or an aromatic bromine compound;(e) 0-20% by weight of a conventional additive;(f) 2-15% by weight of a surfactant; and(g) 15-78% by weight of water.