A table tennis net assembly includes a table tennis net and two opposite net supports each of which includes a base piece mounting thereon a vertical hollow cylinder and a bottom piece cooperating with the base piece to be capable of clamping therebetween a portion of a table; one hollow cylinder mounts therein a coiled spring-biassed shaft fixing one end of the net the other end of which is fixed to a stopper which is to be inserted into the other hollow cylinder which has an axial slit slit through the upper portion thereof.