A composition for forming a thermally conductive material, comprising: a compound represented by General Formula; a phenolic compound; and an inorganic substance, wherein the inorganic substance is for use as an inorganic filler and includes an inorganic nitride or an inorganic oxide, a content of the compound represented by General Formula is 30.0% by mass or greater with respect to a total organic solid content, and the composition does not further comprise an epoxy compound other than the compound represented by General Formula, or in a case where the composition further comprises an epoxy compound other than the compound represented by General Formula, the content of the epoxy compound other than the compound represented by General Formula is up to 60% by mass with respect to the total content of the compound represented by General Formula and the epoxy compound other than the compound represented by General Formula, (X-Z 1 -) m -A-(-Z 2 -Y) n in General Formula, m represents an integer of 3 or greater, n represents an integer of 0 or greater, X represents an epoxy group, Y represents a hydroxyl group, Z 1 and Z 2 each independently represent a single bond or an alkylene group having 1 to 7 carbon atoms, one or more -CH 2 -'s constituting the alkylene group may be substituted with -O-, A represents an (m + n)-valent aliphatic saturated hydrocarbon group, one or more -CH 2 -'s constituting the aliphatic saturated hydrocarbon group may be substituted with -O-, and one or more -CH<'s constituting the aliphatic saturated hydrocarbon group may be substituted with -N<, in a case where there are a plurality of X's, the plurality of X's may be the same as or different from each other, in a case where there are a plurality of Y's, the plurality of Y's may be the same as or different from each other, in a case where there are a plurality of Z 1 's, the plurality of Z 1 's may be the same as or different from each other, and in a case where there are a plurality of Z 2 's, the plurality of Z 2 's may be the same as or different from each other. a compound represented by General Formula; a phenolic compound; and an inorganic substance, wherein the inorganic substance is for use as an inorganic filler and includes an inorganic nitride or an inorganic oxide, a content of the compound represented by General Formula is 30.0% by mass or greater with respect to a total organic solid content, and the composition does not further comprise an epoxy compound other than the compound represented by General Formula, or in a case where the composition further comprises an epoxy compound other than the compound represented by General Formula, the content of the epoxy compound other than the compound represented by General Formula is up to 60% by mass with respect to the total content of the compound represented by General Formula and the epoxy compound other than the compound represented by General Formula, (X-Z 1 -) m -A-(-Z 2 -Y) n in General Formula, m represents an integer of 3 or greater, n represents an integer of 0 or greater, X represents an epoxy group, Y represents a hydroxyl group, Z 1 and Z 2 each independently represent a single bond or an alkylene group having 1 to 7 carbon atoms, one or more -CH 2 -'s constituting the alkylene group may be substituted with -O-, A represents an (m + n)-valent aliphatic saturated hydrocarbon group, one or more -CH 2 -'s constituting the aliphatic saturated hydrocarbon group may be substituted with -O-, and one or more -CH<'s constituting the aliphatic saturated hydrocarbon group may be substituted with -N<, in a case where there are a plurality of X's, the plurality of X's may be the same as or different from each other, in a case where there are a plurality of Y's, the plurality of Y's may be the same as or different from each other, in a case where there are a plurality of Z 1 's, the plurality of Z 1 's may be the same as or different from each other, and in a case where there are a plurality of Z 2 's, the plurality of Z 2 's may be the same as or different from each other.