To obtain an epoxy resin composition for semiconductor sealing, excellent in heat radiating property as well as moldability and heat resistance to soldering.

This epoxy resin composition comprises (A) an epoxy resin, (B) a phenol resin curing agent, (C) an inorganic filler and (D) an amine-based curing accelerator as main components. In the epoxy resin, (A) it contains a biphenyl type epoxy resin represented by the formula (Rs are hydrogen atoms or 1-12C alkyl groups which may be same or different) as a main component, and the component C comprises 55-85 wt.% nitrogen-containing inorganic compound and 15-45 wt.% fused silica and is contained in an amount of 75-90 wt.% based on total resin composition and has 30-300 poise Kouka-type viscosity of the epoxy resin composition at 175°C.