In a liquid epoxy resin composition comprising a liquid epoxy resin, a curing agent, a curing accelerator, and an inorganic filler, the liquid epoxy resin is a mixture of (a) a liquid epoxy resin containing two or less epoxy functional groups and (b) a solid epoxy resin containing two or more epoxy functional groups in a weight ratio (a)/(b) of from 9/1 to 1/4, having a viscosity of up to 10,000 poises at 25° C. as measured by an E type viscometer. The composition is adherent to silicon chips, the cured product is highly resistant to humidity and thermal shocks, and the composition is useful as sealant for semiconductor devices.