To provide a liquid epoxy resin composition having excellent fluidity, reducing the warp after curing, and capable of suppressing the occurrence of bleed, and to provide a semiconductor device using the composition and having excellent solder connection reliability.

The liquid epoxy resin composition contains (A) an epoxy resin liquid at normal temperature, (B) a curing agent and (C) a polyether-based compound, wherein the polyether-based compound (C) has at least one secondary amino groups represented by formula (1) (wherein, X is a linking group; and Ar is an aromatic group) as terminal groups. The semiconductor device is constituted by including an electronic component and a substrate for mounting the electronic component, and has a space between the electronic component and the substrate for mounting the electronic component. The space between the electronic component and the substrate for mounting the electronic component is filled and stuck with a cured product of the liquid epoxy resin composition.