Abstract: A speed bump assembly on a road surface provides a sign to a driver to slow down a car and a warning effect to the driver. The speed bump has a tapered structure and has recesses, grooves or holes defined in opposite sides to enhance shock-absorbing, noise-absorbing and nonskid. Two reflection tabs are attached respective to the opposite sides of the speed bump to provide a warning and reflective effect to a driver to draw the driver's attention when driving. A metal base is attached to the bottom of the speed bump to keep the plastic speed bump from deforming due to expansion when hot and shrinking when cold and to enhance the strength of combination between the road surface.