To provide a sealing resin composition having good moldability, good reliability, no environmental problem, and excellent flame retardancy and to provide a semiconductor device sealed therewith.

There are provided a sealing resin composition essentially consisting of (A) a thermosetting resin, (B) an inorganic filler, a red phosphorus flame retardant prepared by surface-coating red phosphorus with a phenolic resin and aluminum hydroxide, and (D) a magnesium/aluminum inorganic ion exchanger, a zirconium inorganic ion exchanger, or a mixture thereof, wherein component B accounts for 60-90 wt.% of the entire composition, component C accounts for 0.1-10 wt.%, and component D accounts for 0.1-2 wt.% and a semiconductor device sealed therewith.