A temporary silt guard for temporarily enclosing the open upper end of a drop inlet during the construction of a road system in commercial and residential developments is adapted to fit over and seat upon the open end of the drop inlet to enable runoff water to drain into the drop inlet while preventing silt and debris from being carried into and collected therein. The silt guard includes a body portion formed from a series of spaced slats defining radially spaced passages through the silt guard. A filter cover is received over the silt guard, formed from a silt screen material, with the slats of the body portion providing rigidity and strength to the filter cover. The filter cover filters out silt and debris while enabling storm water and runoff to drain into the drop inlet.