A film-forming resin composition for use in encapsulating large-diameter thin-film wafers includes (A) a silicone resin having a weight-average molecular weight of 3,000 to 500,000 and containing repeating units of formula (1) wherein R1 to R4 are monovalent hydrocarbon groups, but R3 and R4 are not both methyl, m and n are integers of 0 to 300, R5 to R8 are divalent hydrocarbon groups, a and b are positive numbers such that a+b=1, and X is a specific divalent organic moiety; (B) a phenolic compound of formula (7) wherein Y is a carbon atom or a tetravalent hydrocarbon group of 2 to 20 carbon atoms, and R13 to R16 are monovalent hydrocarbon groups or hydrogen atoms; and (C) a filler.