The object of the present invention is to provide a polyarylene sulfide composition having excellent thermal conductivity, dimensional stability, heat resistance and low gas property, which is particularly useful to applications of electric parts such as electric and/or electronic parts or automobile electric parts. The present invention relates to a polyarylene sulfide composition comprising a polyarylene sulfide (a), a metal silicon powder (b), a fibrous filler (c), and preferably a release agent (d) and at least one thermally conductive filler (e) selected from the group consisting of a scale-like boron nitride powder (e1) having a hexagonal structure, a coated magnesium oxide powder (e2) coated with a complex oxide of silicon and magnesium and/or a complex oxide of aluminum and magnesium, a high purity magnesite powder (e3) which is a magnesite comprising magnesium carbonate as a main component and has a magnesium carbonate content of from 98 to 99.999% by weight, and graphite (e4).