PROBLEM TO BE SOLVED: To provide a resin composition for thermosetting liquid sealing which enables production of a semiconductor device from a semiconductor element at a low cost and without generation of voids, and an assembling technique of the semiconductor element for the vamp-attached semiconductor element. SOLUTION: A resin composition for thermosetting liquid sealing wherein (1) a spherical inorganic filler has 0.5-12 μm of the average particle size and not more than 20 μm of the maximum particle size, (2) an epoxy resin has not less than 200 for epoxy equivalents and contains the epoxy group having not less than two functions, (3) a thixo ratio (a viscosity ratio at 0.5 rpm and 2.5 rpm by a viscometer) of the resin composition for thermosetting liquid sealing containing diaminodiphenylsulfone is 1 to 2.