PURPOSE: The titled composition having improved heat resistance, mechanical characteristic, sliding properties, workability, and molding and processing properties, consisting of a thermosetting resin comprising and adduct of a polymaleimide shown by a specific formula with an aminophenol, and a fluorine- contained resin.

CONSTITUTION: (A) 30W70wt% thermosetting resin comprising an addition reaction product of a polymaleimide (e.g., ethylenebismaleimide, etc.) shown by the formula I (R1 is n-functional organic group; X1 and X2 are H, halogen, or organic group; n≤2) with an aminophenol shown by the formula II (R2 is H, halogen, or organic group; m is 1W5) obtained by reaction under heating generally at 50W200°C with stirring, and an epoxy compound (e.g., bisphenol A type epoxy resin, etc.) containing ≥2 epoxy groups in one molecule is blended with (B) 70W30wt% composite filter consisting of a fluorine-contained resin (e.g., tetrafluoroethylene resin, etc.) and granular phenolic resin, to give the aimed composition.